Systems and methods for treatment of fluid overload

ABSTRACT

Various systems and methods are provided for reducing pressure at an outflow of a duct, such as the thoracic duct or the lymphatic duct, for example, the right lymphatic duct. A catheter system can be configured to be at least partially implanted within a vein of a patient in the vicinity of an outflow port of a duct of the lymphatic system. The catheter system includes first and second selectively deployable restriction members each configured to be activated to at least partially occlude the vein within which the catheter is implanted and to thus restrict fluid within a portion of the vein. The catheter system includes an impeller configured to be driven by a motor to induce a low pressure zone between the restriction members by causing blood to be pumped through the catheter when the restriction members occlude the vein.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Patent Application No.62/415,684 entitled “Systems And Methods For Treatment of PulmonaryEdema” filed Nov. 1, 2016, U.S. Patent Application No. 62/415,964entitled “Systems and Methods for Treatment of Edema” filed Nov. 1,2016, and U.S. Patent Application No. 62/445,231 entitled “Catheter withImpeller for Treatment of Edema” filed Jan. 11, 2017, which are herebyincorporated by reference in their entireties.

FIELD

The present disclosure relates generally to systems and methods forfluid overload relief and, in particular, for treatment of edema.

BACKGROUND

The lymphatic system is part of the circulatory system in conjunctionwith the arterial and venous systems. A primary function of thelymphatic system is to drain excessive interstitial fluid back into thevenous system at two main locations: the thoracic duct and the lymphaticduct (the right lymphatic duct), which drain into the left and rightbifurcation of the internal Jugular and subclavian veins, respectively.

Under normal circulatory conditions of the arterial and venous systems,the interstitial fluid volume balance is maintained and the lymph fluidis cleared back through the lymphatic system. In pathological conditionssuch as acute cardiogenic fluid overload, acutely decompensated heartfailure and chronic heart failure, the capillary hydrostatic pressureand the venous pulmonary pressure can become elevated and fluid flowsexcessively out of the blood vessels and into the interstitial andalveolar spaces. The pressure gradient between the initial lymphaticsand at the outflow of the thoracic duct and a lymphatic duct is reduced,and the lymphatic system cannot clear the additional fluid whichaccumulates in the air spaces of the lungs. This is a life threateningcondition, as gas exchange is impaired to the extent that it may lead torespiratory failure.

Current treatment methods require extended hospitalization and treatmentwith loop diuretics and/or vasodilators. Oftentimes patients must alsoreceive supplemental oxygen or, in more extreme cases, requiremechanical ventilation. Many of these treatment methods are less thanideal because the edema is not always alleviated rapidly enough and formany patients renal function is adversely affected. A significantpercentage of patients do not respond to this treatment and asignificant percentage must be readmitted to a hospital within thirtydays.

A significant problem with current treatment protocol is that it isbased on the need to reduce intravascular blood pressure to moveinterstitial and lymphatic fluid back into the vasculature. Thereduction of intravascular blood pressure may lead to hypotension andmay activate the Renin Angiotenesin Aldesterone System, which may leadback to an increase in blood pressure or to worsening of renal function.Eventually, this cycle leads to diuretic resistance and the worsening ofrenal function in almost 30% of admitted patients.

Accordingly, there remains a need for improved methods and devices forsystems and methods for treating fluid overload.

SUMMARY

In one aspect, a medical system for treating fluid overload is providedthat in some embodiments includes a catheter configured for at leastpartial placement within a vein of a patient, and a motor. The catheterincludes an indwelling catheter tube having a lumen extendingtherethrough, the lumen configured to receive a drive shaft having adistal end thereof operatively coupled to an impeller. The catheter alsoincludes a first selectively deployable restriction member adjacent tothe impeller, the first selectively deployable restriction memberdisposed around a first portion of the catheter shaft, and a secondselectively deployable restriction member proximal to the firstrestriction member, the second selectively deployable restriction memberdisposed around a second portion of the catheter tube. The motor isconfigured to rotate the drive shaft and thereby rotate the impellercoupled to the drive shaft.

The system can vary in numerous ways. For example, the impeller can bedisposed distally to the first restriction member. As another example,the system can further include a flow regulation component disposedproximally to the second restriction member and configured to directfluid from an upstream side of the second restriction member to adownstream side of the second restriction member, the flow regulationcomponent having at least one opening configured to allow fluidtherethrough. The flow regulation component can be operatively coupledto the second restriction member. The flow regulation component can beconfigured to direct fluid through a lumen of the second restrictionmember.

In some embodiments, the system further includes a controller configuredto control operation of the motor based on measurements of fluidpressure acquired by at least one pressure sensor located between thefirst and second restrictors.

In some embodiments, the first and second restriction members eachinclude a selectively expandable element configured to be expandedradially. In some embodiments, the catheter tube has at least oneinflation lumen configured to deliver a fluid or gas to activate thefirst and second restriction members.

The first restriction member can have a first inner lumen and the secondrestriction member can have a second inner lumen, the first and secondinner lumens allow fluid to pass therethrough. In some embodiments, thefirst inner lumen of the first restriction member has a diameter that isgreater than a diameter of the second inner lumen of the secondrestriction member. In some embodiments, an inner wall of the firstrestriction member defining the first inner lumen of the firstrestriction member has a shaft holder coupled thereto, the shaft holderbeing configured to receive the catheter tube thereto so as to maintaina position of the catheter tube. In some embodiments, the system furtherincludes a membrane extending between the first restriction member andan impeller housing configured to encompass the impeller, the membranebeing coupled to the first restriction member and defining a tunneltherethrough. The membrane can have various configurations. For example,in some embodiments, the membrane can be generally distally tapered.

The impeller housing can also have various configurations. For example,in some embodiments, the impeller housing includes at least one openingat a distal end thereof such that fluid passing through the impellerhousing from a proximal end thereof towards the distal end thereof canexit the impeller housing through the at least one opening.

In another aspect, a catheter system for treating fluid overload isprovided that in some embodiments includes a catheter configured for atleast partial placement within a vein of a patient, the catheterincluding an indwelling catheter tube having a lumen extendingtherethrough, the lumen configured to receive a drive shaft having adistal end thereof operatively coupled to an impeller, a firstselectively deployable restriction member adjacent to the impeller anddisposed around the catheter tube, a second selectively deployablerestriction member proximal to the first restriction member and disposedaround the catheter tube. The catheter also includes a fluid flowpassage defined by a second inner lumen of the second restrictionmember, a first inner lumen of the first restriction member, an impellerhousing having the impeller in a tunnel thereof, and a membraneextending between the first restriction member and the impeller housing.

The system can vary in numerous ways. For example, the system canfurther include a motor operatively coupled to the drive shaft andconfigured to rotate the drive shaft and thereby rotate the impellercoupled to the drive shaft. As another example, the system can furtherinclude an atraumatic tip extending distally from the impeller housing.

In a further aspect, a method for treating fluid overload is providedthat in some embodiments includes implanting a catheter within a vein ofa patient, the catheter extending from a first position at one side ofan outflow port of a duct to a second position at another side of theoutflow port; creating a first restriction within the vein proximal to adistal region of the catheter; creating a second restriction within thevein proximal to a first restriction; and activating an impeller of thecatheter so as to define a localized low pressure zone between thesecond and first restrictions and adjacent to the outflow port of theduct, the low pressure zone being created by causing fluid to pass froma proximal side of the second restriction to a distal side of the secondrestriction and from a proximal side of the first restriction to adistal side of the first restriction.

The method can vary in numerous ways. For example, creating the firstrestriction can include deploying a first selectively expandablerestrictor and creating the second restriction can include deploying asecond selectively expandable restrictor such that the fluid passes fromthe proximal side of the second restriction to the distal side of thefirst restriction by passing through inner lumens of the first andsecond restrictors and towards the impeller. As another example, thevein can be at least one of an internal jugular vein and a subclavianvein. As a further example, the duct includes one of a thoracic or aright lymphatic duct.

In some embodiments, various systems and methods are provided forreducing pressure at an outflow of a duct such as the thoracic duct orthe lymphatic duct, for example, the right lymphatic duct. An indwellingcatheter can be configured to be at least partially implanted within avein of a patient in the vicinity of or within an outflow port of a ductof the lymphatic system. The catheter can include first and/or secondrestrictors each configured to at least partially occlude the veinwithin which the catheter is implanted and to thus restrict fluid withinthe vein when the restrictors are activated. The catheter can include apump including an impeller disposed within a catheter shaft. Theimpeller can be positioned at various locations with respect to thefirst and second restrictors.

In one aspect, a system for treating edema is provided that in someembodiments includes an indwelling catheter configured for at leastpartial placement within a vein of a patient, the indwelling catheterhaving a catheter shaft, the catheter shaft having one or more inletopenings, a first selectively deployable restriction member, a secondselectively deployable restriction member, and a lumen extending throughthe catheter shaft, the lumen being in fluid communication with thefirst and the second restriction members, wherein the first restrictionmember is disposed at a proximal end of the lumen and the secondrestriction member is disposed at a distal end of the lumen. The systemalso includes a pump configured to create a pressure differential towithdraw fluid from the inlet opening to withdraw a fluid within thevein from venous circulation and to return the fluid to venouscirculation through the catheter system, a motor configured to cause thepump to operate, and a controller configured to control operation of themotor.

The system can vary in a number of ways. For example, the system caninclude an impeller associated with the catheter shaft. The impeller canbe positioned proximally to the first restriction member, distally tothe second restriction member, or between the first and secondrestriction members. As yet another example, the lumen can beexpandable. As a further example, the lumen can include an expandablesegment extending between an inlet opening of the lumen and the impeller

In some embodiments, the controller can operate using measurementsobtained by at least one sensor, the measurements including motorcurrent and voltage consumption. In some embodiments, the first andsecond restrictors each include a balloon.

In some embodiments, a medical system is provided that includes acatheter shaft configured to be positioned within a vein of a patient, afirst selectively deployable restrictor coupled to the catheter shaftand configured to be positioned within the vein and a second selectivelydeployable restrictor coupled to the catheter shaft at a location distalto the first restrictor such that a distance spans between the first andsecond restrictors, the second restrictor being configured to bepositioned within the vein. The medical system also includes at leastone inlet opening formed through a sidewall of the catheter shaft at alocation between the first and second restrictors, and a pump configuredto facilitate suction of fluid into the catheter shaft through the atleast one inlet opening.

The medical system can vary in a number of ways. For example, the firstand second restrictors can each include a balloon. As another example,the medical system can further include at least one inflation lumenextending along the catheter shaft, the at least one inflation lumenbeing in fluid communication with the first and second restrictors. Theat least one inflation lumen can include a single lumen in fluidcommunication with both of the first and second restrictors. As yetanother example, the first restrictor can be movable between anactivated configuration in which the first restrictor has a firstdiameter and a relaxed configuration in which the first restrictor has asecond diameter that is less than the first diameter, and the secondrestrictor is movable between an activated configuration in which thesecond restrictor has a third diameter and a relaxed configuration inwhich the second restrictor has a fourth diameter that is less than thethird diameter.

In some embodiments, the system further includes an impeller associatedwith the catheter shaft. The impeller can be disposed proximally to thefirst restrictor, distally to the second restrictor, or between thefirst and second restrictors.

In some embodiments, the impeller is disposed proximally to the firstrestrictor, and the catheter shaft includes an inflation lumen, theinflation lumen comprising an expandable segment disposed between the atleast one inlet opening and the impeller.

In some embodiments, the pump is configured to be positioned within thevein. In some embodiments, the system further includes a controllerconfigured to actuate the pump. The controller can be configured toactuate the pump in response to user operation of a control external tothe body of the patient. In some embodiments, the system furtherincludes a pressure sensor configured to be implanted in the body of thepatient, the controller being configured to actuate the pump in responseto a pressure measured by the pressure sensor being different (e.g.,smaller or greater) than a predefined threshold.

In some embodiments, the system further includes a pressure sensorconfigured to be implanted in the body of the patient, the controllerbeing configured to control a speed of operation of the pump dependingon a pressure measured by the pressure sensor. In some embodiments, thevein includes an internal jugular vein, a subclavian vein, an innominatevein or an external jugular vein.

In some embodiments, a medical method is provided that includesimplanting the catheter shaft at least at least partially within a veinof a patient such that the first restrictor is positioned upstream of anoutflow port of a duct of the patient's lymphatic system and such thatthe second restrictor is positioned downstream of the outflow port ofthe duct.

The medical method can vary in many ways. For example, the method canfurther include activating the first restrictor such that the firstrestrictor occludes the vein at a first occlusion site, and activatingthe second restrictor such that the second restrictor occludes the veinat a second occlusion site. As another example, the method can furtherinclude activating the first restrictor by inflating the firstrestrictor, and activating the second restrictor by inflating the secondrestrictor. In some embodiments, activating the first restrictorincludes radially expanding the first restrictor, and activating thesecond restrictor includes radially expanding the second restrictor. Insome embodiments, the method further includes actuating the pump,thereby creating a low pressure zone between the first and secondrestrictors. The duct can include a thoracic duct or a lymphatic duct(e.g., a right lymphatic duct), and the vein can include both right andleft internal jugular veins, a subclavian vein, an innominate vein, oran external jugular vein.

In another aspect, a medical system is provided that in some embodimentsincludes a catheter shaft configured to be positioned within a vein of apatient, at least one restrictor, and a pump. The at least onerestrictor is coupled to the catheter shaft and is configured to bepositioned within the vein, the at least one restrictor being movablebetween an activated configuration in which the at least one restrictorhas a first diameter and a relaxed configuration in which the at leastone restrictor has a second diameter that is less than the firstdiameter, the at least one restrictor being configured to occlude fluidflow through the vein when the at least one restrictor is in theactivated configuration within the vein. The pump is configured to pumpfluid through the catheter shaft regardless of whether the at least onerestrictor is in the activated configuration or the relaxedconfiguration.

The medical system can vary in many ways. For example, the at least onerestrictor can include a single restrictor. As another example, the atleast one restrictor can include a balloon. As yet another example, thesystem can include at least one inflation lumen extending along thecatheter shaft, the at least one inflation lumen being in fluidcommunication with the at least one restrictor. As a further example,the system can include an impeller associated with the catheter shaft.

In some embodiments, the pump is configured to be positioned within thevein. In some embodiments, the system further includes a controllerconfigured to actuate the pump. The controller can be configured toactuate the pump in response to user operation of a control external tothe body of the patient.

In some embodiments, the system can further include a pressure sensorconfigured to be implanted in the body of the patient, the controllerbeing configured to actuate the pump in response to a pressure measuredby the pressure sensor exceeding a predefined threshold. The vein caninclude an internal jugular vein or a subclavian vein.

In some embodiments, a medical method is provided that includesimplanting the catheter shaft at least at least partially within a veinof a patient such that the at least one restrictor is positionedupstream of an outflow port of a duct of the patient's lymphatic system.

The medical method can vary in many ways. For example, the method canfurther include activating the at least one restrictor such that the atleast one restrictor occludes the vein. As another example, the methodcan further include activating the at least one restrictor by inflatingthe at least one restrictor. As a further example, the method caninclude activating the at least one restrictor by radially expanding theat least one restrictor. In some embodiments, the method furtherincludes actuating the pump, thereby creating a low pressure zoneadjacent the duct.

Various systems and methods are provided for reducing pressure at anoutflow of a duct such as the thoracic duct or the lymphatic duct (e.g.,the right lymphatic duct). An indwelling catheter can be configured tobe at least partially implanted within a vein of a patient in thevicinity of or inside an outflow port of a duct of the lymphatic system.

In some aspects, a system for treating edema is provided that in someembodiments includes an indwelling catheter configured for placementwithin a vein of a patient. The indwelling catheter includes a driveshaft having a lumen extending therethrough, wherein a distal portion ofthe drive shaft is operatively coupled to an impeller. The indwellingcatheter also includes a first selectively deployable restriction memberadjacent and proximal to the impeller, the first restriction memberhaving a membrane operatively coupled thereto and configured to directfluid from an upstream side of the first restriction member to theimpeller. The indwelling catheter further includes a second selectivelydeployable restriction member proximal to the first restriction member,the second restriction member being operatively coupled to a flowregulation component configured to direct a controlled volume of fluidfrom an upstream side of the second restriction member to a downstreamside of the second restriction member. The system also includes a motorconfigured to rotate the drive shaft and the impeller.

The system can vary in a number of ways. For example, the membrane canbe a conical membrane at least partially wrapped around the firstrestriction member. As another example, the flow regulation componentcan have at least one opening configured to allow fluid therethrough. Asyet another example, the system can further include a controllerconfigured to control operation of the motor. The controller can operateusing measurements obtained by at least one sensor, the measurementsincluding fluid pressure.

In some embodiments, the first and second restriction members eachinclude a balloon. In some embodiments, the vein is an internal jugularvein or a subclavian vein. In some embodiments, the first restrictionmember is part of a distal assembly, and the second restriction memberis part of a separate, proximal assembly.

In one aspect, a system for treatment of interstitial fluid overload,which can lead to edema, is provided that in some embodiments includes apump configured to be implanted in a body of a patient, an inflow tube,an outflow tube, and power source. The inflow tube is fluidicallycoupled to an inflow port of the pump and configured to be implantedinto the body of the patient so as to bring the inflow port into fluidcommunication with a thoracic duct or a right lymphatic duct of thepatient. The outflow tube is fluidically coupled to an outflow port ofthe pump and configured to be implanted into the body of the patient soas to bring the outflow port into fluid communication with a vein in thebody of the patient such that the pump is operative to pump fluid fromthe thoracic duct or the right lymphatic duct to the vein. The powersource is configured to be implanted in the body of the patient andconfigured to provide power to the pump.

The system can vary in a number of ways. For example, the power sourcecan include a battery. The battery can be a rechargeable battery. Asanother example, the pump can be configured to continuously pump thefluid from the thoracic duct to the vein.

In some embodiments, the system can further include a controllerconfigured to activate the pump. The controller can be configured toactuate the pump in response to user operation of a control external tothe body of the patient.

In some embodiments, the system can further include a pressure sensorconfigured to be implanted in the body of the patient, the controllerbeing configured to actuate the pump in response to a pressure measuredby the pressure sensor exceeding a predefined threshold. In someembodiments, the system can further include a pressure sensor configuredto be implanted in the body of the patient, the controller beingconfigured to control a speed of operation of the pump depending on apressure measured by the pressure sensor.

The pump can vary in a number of ways. For example, the pump can includea pulsatile pump. As another example, the pump can be configured to pumpfluid at a rate in a range of about 100 to 1000 ml/hour. As anotherexample, the pump can be configured to pump fluid at a rate of about 300ml/hour. As yet another example, the pump can be configured to pumpfluid at a rate of about 500 ml/hour.

In another aspect, a method of treating edema is provided that in someembodiments includes implanting a pump in a body of a patient, the pumpbeing operable to convey a bodily fluid from an inflow port of the pumpto an outflow port of the pump, arranging a first tube in fluidcommunication with the inflow port to be in fluid communication with athoracic duct of the patient, arranging a second tube in fluidcommunication with the outflow port to be in fluid communication with avein of the patient such that the pump is operable to convey fluid fromthe thoracic duct to the vein, and implanting a power source configuredto be implanted in the body of the patient and configured to providepower to the pump.

The method can vary in a number of ways. For example, the method canfurther include actuating the pump, thereby causing the pump to conveythe fluid from the thoracic duct to the vein of the patient, the fluidincluding lymph. As another example, the pump can be actuated inresponse to user operation of a control external to the body of thepatient. The pump can be configured to be activated periodically orcontinuously.

In some embodiments, the vein includes one of the patient's subclavianvein and internal jugular vein. In some embodiments, the method furtherincludes implanting a pressure sensor in a location within the body ofthe patient that enables the pressure sensor to measure pressure in adesired region of the body of the patient. In some embodiments, themethod further includes measuring the pressure in the desired regionusing the pressure sensor, and activating the pump in response to themeasured pressure exceeding a predefined threshold. In some embodiments,the method further includes measuring the pressure in the desired regionusing the pressure sensor, and controlling a speed of operation of thepump depending on the measured pressure.

In some embodiments, the power source includes a battery. The batterycan be a rechargeable battery. The method can further include activatingthe pump to cause the pump to continuously pump the fluid from thethoracic duct to the vein.

BRIEF DESCRIPTION OF DRAWINGS

This disclosure will be more fully understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a schematic cross-sectional view of one embodiment of acatheter implanted in a vein of a patient;

FIG. 2 is a schematic cross-sectional view of an embodiment of acatheter in accordance with the described techniques;

FIG. 3 is a schematic cross-sectional view of another embodiment of acatheter in accordance with the described techniques;

FIG. 4 is a schematic cross-sectional view of yet another embodiment ofa catheter in accordance with the described techniques;

FIG. 5 is a schematic cross-sectional view of yet another embodiment ofa catheter in accordance with the described techniques;

FIG. 6 is a schematic cross-sectional view of yet another embodiment ofa catheter in accordance with the described techniques;

FIG. 7 is a perspective view of an embodiment of an implantable cathetersystem;

FIG. 8 is an exploded view of the implantable system of FIG. 7;

FIG. 9A is a side view of a distal portion of the implantable system ofFIG. 7;

FIG. 9B is a perspective view of the distal portion of FIG. 9A;

FIG. 10A is a perspective view of a portion of a proximal assembly ofthe implantable system of FIG. 7;

FIG. 10B is cross-section of a portion of the proximal assembly of FIG.10A;

FIG. 11 is a perspective view of an embodiment of an implantablecatheter system, showing the implantable system implanted in a patient'sbody;

FIG. 12 is a perspective view of another embodiment of an implantablecatheter system, showing the implantable system implanted in a patient'sbody;

FIG. 13 is a cross-sectional view of a main catheter of the implantablecatheter system of FIG. 7;

FIG. 14 is a cross-sectional view of a drive shaft of the implantablecatheter system of FIG. 7;

FIG. 15 is a side view of an impeller of the implantable catheter systemof FIG. 7;

FIG. 16 is a side view of an impeller housing of the implantablecatheter system of FIG. 7;

FIG. 17 is a perspective view of an embodiment of an impeller housing;

FIG. 18 is a side view of a membrane of an implantable catheter system;

FIG. 19 is a cross-sectional view of a restrictor of the implantablecatheter system of FIG. 7;

FIG. 20 is a perspective view of a drive shaft holder associated withrestrictor of FIG. 19;

FIG. 21 is a side, partially transparent view of a distal tip of theimplantable system of FIG. 7;

FIG. 22 is a perspective view of a motor configured to drive an impellerof an implantable system;

FIG. 23A is a perspective view of a system in accordance with someembodiments, the system including an implantable catheter system shownimplanted in a patient;

FIG. 23B is an enlarged side view of the implantable catheter system ofFIG. 23A;

FIG. 24 is a partially transparent side view of the implantable cathetersystem of FIG. 23A;

FIG. 25 is a partially transparent side view of a distal portion of theimplantable catheter system of FIG. 24;

FIG. 26A is a cross-sectional side view of a bearing disposed in animpeller housing of the implantable catheter system of FIG. 24;

FIG. 26B is a cross-sectional view of a catheter shaft of a cathetersystem in accordance with the described techniques;

FIG. 26C is a perspective view of a proximal restriction member of theimplantable catheter system of FIG. 24;

FIG. 27 is a cross-sectional side view of a portion of the implantablecatheter system of FIG. 24;

FIG. 28 is a perspective view of an embodiment of an implantablecatheter system, showing the implantable system implanted in a patient'sbody;

FIG. 29 is a perspective view of another embodiment of an implantablecatheter system, showing the implantable system implanted in a patient'sbody;

FIG. 30 is a schematic perspective view of an embodiment of animplantable device implanted in a body;

FIG. 31 is a partially transparent, cross-sectional view of anembodiment of a tube that can be used in the implantable pump system ofFIG. 30;

FIG. 32 is a partially transparent, cross-sectional view of a portion ofthe implantable device of FIG. 30;

FIG. 33 is another perspective view of the implantable device of FIG.30, illustrating the implantable device including an antimicrobial cuff;

FIG. 34A is a perspective view of a stent that can be used in connectionwith the implantable device of FIG. 30;

FIG. 34B is a perspective view of another stent that can be used inconnection with the implantable device of FIG. 30;

FIG. 34C is a schematic side diagram illustrating deployment of a stent;

FIG. 34D is another schematic diagram illustrating deployment of thestent of FIG. 34C;

FIG. 35 is a flowchart of one embodiment of a method of treating edemausing an implantable device in accordance with the described techniques;

FIG. 36 is a schematic perspective view of an embodiment of animplantable port implanted in a patient's body; and

FIG. 37 is another perspective view of the implantable port of FIG. 36.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those skilled in the art will understand that the devices andmethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the present invention is defined solely by the claims. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments. Suchmodifications and variations are intended to be included within thescope of the present invention.

Reference throughout the specification to “various embodiments,” “someembodiments,” “one embodiment,” or “an embodiment,” or the like, meansthat a particular feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodiment.Thus, appearances of the phrases “in various embodiments,” “in someembodiments,” “in one embodiment,” or “in an embodiment,” or the like,in places throughout the specification are not necessarily all referringto the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments. Thus, the particular features, structures, orcharacteristics illustrated or described in connection with oneembodiment may be combined, in whole or in part, with the featuresstructures, or characteristics of one or more other embodiments withoutlimitation.

It will be appreciated that the terms “proximal” and “distal” may beused throughout the specification with reference to a clinicianmanipulating one end of an instrument used to treat a patient. The term“proximal” refers to the portion of the instrument closest to theclinician and the term “distal” refers to the portion located furthestfrom the clinician. It will be further appreciated that for concisenessand clarity, spatial terms such as “vertical,” “horizontal,” “up,” and“down” may be used herein with respect to the illustrated embodiments.However, surgical instruments may be used in many orientations andpositions, and these terms are not intended to be limiting and absolute.

Further, in the present disclosure, like-named components of theembodiments generally have similar features, and thus within aparticular embodiment each feature of each like-named component is notnecessarily fully elaborated upon. Additionally, to the extent thatlinear or circular dimensions are used in the description of thedisclosed systems, devices, and methods, such dimensions are notintended to limit the types of shapes that can be used in conjunctionwith such systems, devices, and methods. A person skilled in the artwill recognize that an equivalent to such linear and circular dimensionscan easily be determined for any geometric shape. Sizes and shapes ofthe systems and devices, and the components thereof, can depend at leaston the anatomy of the subject in which the systems and devices will beused, the size and shape of components with which the systems anddevices will be used, and the methods and procedures in which thesystems and devices will be used.

Various systems and methods are provided for reducing pressure at anoutflow of a duct such as the thoracic duct or a lymphatic duct, forexample, the right lymphatic duct. In general, the systems and methodsmay be effective to relieve fluid overload in patients with diagnosededema conditions and in patients at risk of developing edema, such aspulmonary edema, by lowering an outflow pressure in a region around thepatient's duct outflow. As a result of lowering the outflow pressure atthe thoracic and/or lymphatic ducts, higher lymphatic return will beachieved, enabling the lymphatic vessel flow to be at or near normallevels. The lymphatic drainage can be enhanced without overloading thevenous system or elevating its pressure. The systems and methods may beeffective to rapidly alleviate conditions of the edema and increase thepatient response rate. In an exemplary embodiment, the systems andmethods may be particularly useful to treat acute pulmonary edema orfluid overload as seen in most patients with acute decompensated heartfailure (ADHF), however a person skilled in the art will appreciate thatthe systems and methods can be used in various procedures for treating alymphatic system fluid clearance imbalance.

In one embodiment, an indwelling catheter can be configured to be atleast partially implanted (e.g., partially implanted or fully implanted)within a vein of a patient in the vicinity of an outflow port of a ductof the lymphatic system, e.g., in the vicinity of an outflow port of thethoracic duct or in the vicinity of an outflow port of the lymphaticduct, for example, the right lymphatic duct. Exemplary materials fromwhich the catheter can be made include polyurethanes or polyamides. Thecatheter can include first and second restrictors (also referred toherein as “restriction members”) each configured to at least partiallyocclude the vein within which the catheter is implanted and thus torestrict fluid flow within the vein when the restrictors are activated.The restrictors can each be configured to move between an activatedconfiguration, in which the restrictor occludes the vein, and a relaxedconfiguration, in which the restrictor does not occlude the vein. Therestrictors can each be in the relaxed configuration during implantationof the catheter to ease introduction of the catheter into the patient'sbody and into the vein. Each of the restrictors can include a balloonconfigured to be inflated where in the relaxed configuration the balloonis not inflated and in the activated configuration in which the balloonis inflated.

The restrictors can be made from any one or more of a variety ofmaterials configured to expand upon the delivery of a fluid thereto andto contract upon the withdrawal of the fluid. Exemplary materials fromwhich the balloon can be made include polymeric materials such as PEBAX,silicones, polyurethanes, and nylons. The catheter can include at leastone inflation lumen through which an inflation fluid (e.g., air, liquid,etc.) can be introduced to inflate/deflate the restrictors. The at leastone inflation lumen can include one lumen in fluid communication withboth of the restrictors such that the restrictors can be simultaneouslyinflated/deflated, or can include first and second lumens with the firstlumen in fluid communication with the first restrictor and the secondlumen in fluid communication with the second restrictor such that therestrictors can be selectively inflated simultaneously or sequentially.The catheter can include a pump, such as an axial motor pump, configuredto pump fluid through the catheter. The catheter can be coupled to amotor configured to drive the pump. The motor can be included in thecatheter (e.g., within a shaft of the catheter) and be configured to beimplanted with the catheter, or the motor can be located outside of thecatheter (e.g., outside of the catheter's shaft) and be configured to belocated outside of the patient rather than be implanted therein.

In one embodiment of using the catheter, the catheter can be positionedat a desired location within the vein. The first and second restrictorscan then each be activated (simultaneously or sequentially) to move fromthe relaxed configuration to the activated configuration. The first andthe second restrictors, when activated so as to provide two occlusionswithin the vein, define a low pressure zone therebetween within aportion of the vein in which the catheter is positioned. Higher pressurezones or pressure zones having the same pressure as before the catheterwas operated accordingly exist on either side of the restrictors. Themotor can drive the pump to induce the low pressure zone by causingfluid to be pumped through the catheter. The fluid is pumped at the ratethat is higher than a rate of a natural blood flow in the vein. Thecatheter and the restrictors can be positioned within the vein such thatthe low pressure zone is adjacent to an outflow port of a duct (e.g.,the thoracic duct or the lymphatic duct, such as the right lymphaticduct) to allow fluid to pass from the lymph duct outflow port to theportion of the catheter housed within the vein so that fluid can flowout of the catheter.

In at least some embodiments, the restrictor(s) of a catheter can beinflated and deflated from time to time to enable free flow of blood ina patient's vein in which the restrictor(s) are positioned and thusenable the system to stop working for a period of time. This period oftime can be required in such treatments to allow for the assessment ofthe patient's clinical condition, allow the patient to undergo othertreatments or enable him to go to the bathroom and/or to wash anystagnation points that might have occurred.

The catheters described herein can be configured to be placed in apatient's body for up to about seventy-two hours, e.g., the catheter canbe indwelled in the body for up to about seventy-two hours. The cathetersystems described herein that include the catheters can be operated in atreatment time period in a range of about 6 to 8 hours. At the end ofeach treatment period, the restrictors are deflated, the catheter can befilled with a heparin catheter locking solution, and an assessment ofthe patient's clinical condition can be performed. The catheter systemcan be operated again if desired by medical personnel. Within theindwelling period of the catheter, a number of treatment periods can bein a range of 3 to 6 cycles, e.g., for a maximum of about forty hours ofoperation within a seventy-two hour indwelling period.

A person skilled in the art will appreciate that the systems and methodsdisclosed herein can be used with a variety of surgical devices,including measuring devices, sensing devices, locator devices, insertiondevices, etc.

FIG. 1 illustrates one embodiment of a catheter 1 that includes at leastone restrictor 2 a, 2 b. The at least one restrictor includes first andsecond restrictors 2 a, 2 b in this illustrated embodiment, which eachinclude a balloon configured to be inflated (corresponding to anactivated configuration) and deflated (corresponding to a relaxedconfiguration). The first and second restrictors 2 a, 2 b can be spaceda distance apart from one another along a longitudinal length of thecatheter 1 such that one of the restrictors 2 b is more distal than theother of the restrictors 2 a. The distance between the first and secondrestrictors 2 a, 2 b can define a length of a low pressure zone that canbe created when the catheter 1 is implanted within a vein. FIG. 1 showsthe catheter 1 positioned within an internal jugular vein 3 of a patientwith the distal restrictor 2 b positioned distal to an outflow port 4 pof the patient's thoracic duct 4 and the proximal restrictor 2 apositioned proximal to the outflow port 4 p of the patient's thoracicduct 4. The low pressure zone defined between the proximal and distal(first and second) restrictors 2 a, 2 b can thus be located adjacent theoutflow port 4 p of the thoracic duct 4. The proximal restrictor 2 abeing positioned proximal to (e.g., upstream) of the outflow port 4 p ofthe thoracic duct 4 may help prevent back flow from the patient'ssubclavian vein 5 while providing the low pressure zone and benefit(s)thereof. The catheter 1 can be similarly positioned on a right side ofthe patient with the distal restrictor 2 b positioned distal to anoutflow port of the patient's subclavian vein 5 and an outflow port ofthe patient's lymphatic duct, such as, for example, the right lymphaticduct, (not shown) and the proximal restrictor 2 a positioned proximal tothe outflow port of the patient's subclavian vein 5 and the outflow portof the patient's lymphatic duct.

The catheter 1 can include at least one inflation lumen (omitted fromFIG. 1 for clarity of illustration) configured to facilitate inflationof the first and second restrictors 2 a, 2 b, e.g., to facilitatemovement of the restrictors 2 a, 2 b between the activated and relaxedconfigurations. The first and second restrictors 2 a, 2 b are shown inthe activated configuration in FIG. 1 with the first and secondrestrictors 2 a, 2 b each abutting an internal surface of the jugularvein 3 so as to provide two, spaced-apart occlusions therein.

The catheter 1 can include a shaft 7 having a lumen 7L, as shown in thisillustrated embodiment, configured to communicate fluid therethrough soas to accommodate the flow of fluid in a vein in which the catheter 1 isimplanted. The shaft 7 can have a variety of sizes, such as having adiameter that is in the range of about 8 to 18 Fr (e.g., about 8 Fr,equal to or less than about 12 Fr, etc.) and having a length in therange of about 25 to 40 cm.

The first and second restrictors 2 a, 2 b can be attached to andsurround the shaft 7. The first and second restrictors 2 a, 2 b can eachbe formed in the shape of a torus, as in this illustrated embodiment, tofacilitate the surrounding of the shaft 1 and/or to help preventcompression of the restrictors 2 a, 2 b when they are moved radiallyoutward during expansion thereof and thereby thus overcoming a possibletendency for the restrictors 2 a, 2 b to collapse in response to anexternal pressure. The first and second restrictors 2 a, 2 b can,however, have other shapes.

The catheter 1 can have a first or distal suction inlet 8 d formedthrough the shaft's sidewall. The distal suction inlet can be incommunication with the lumen 7L so as to allow fluid to enter the lumen7L therethrough, as shown in FIG. 1 by four arrows at the distal suctioninlet 8 d pointing inward toward the lumen 7L. The distal suction inlet8 d can include any number of openings formed through the shaft'ssidewall. The openings can have any of a variety of configurations,e.g., slits, circular holes, ovular holes, rectangular slots, etc. Thedistal suction inlet 8 d can be located along the catheter'slongitudinal length at a position between the first and secondrestrictors 2 a, 2 b. The distal suction inlet 8 d can thus be locatedwithin the low pressure zone. In an exemplary embodiment, as shown inFIG. 1, in use, the distal suction inlet 8 d can be positioned adjacentthe outflow ports 4 p, 5 p of the thoracic duct 4 and the subclavianvein 5 so as to allow fluid exiting the outflow ports 4 p, 5 p to enterthe catheter 1.

The catheter 1 can include a second or proximal suction inlet 8 p formedthrough the shaft's sidewall. The proximal suction inlet 8 p can be incommunication with the lumen 7L so as to allow fluid to enter thecatheter's lumen 7L therethrough, as shown in FIG. 1 by two arrows atthe proximal suction inlet 8 p pointing inward toward the lumen 7L. Theproximal suction inlet 8 p can include any number of openings formedthrough the shaft's sidewall. The openings can have any of a variety ofconfigurations, e.g., slits, circular holes, ovular holes, rectangularslots, etc. The proximal suction inlet 8 p can be located proximal tothe distal suction inlet 8 d and proximal to the first and secondrestrictors 2 a, 2 b. In an exemplary embodiment, as shown in FIG. 1, inuse, the proximal suction inlet 8 p can be positioned proximal to theoutflow ports 4 p, 5 p of the thoracic duct 4 and the subclavian vein 5,e.g., upstream thereof. The proximal suction inlet 8 p may thus allowfor regular fluid flow through the jugular vein 3 even when the proximalrestrictor 2 a is activated and occluding the jugular vein 3.

The catheter 1 can include a distal end 1 d configured to be implantedwithin the patient's body (e.g., within the jugular vein 3, as shown inthis illustrated embodiment) and a proximal end 1 p configured to not beimplanted and instead be located outside the patient's body when thecatheter's distal end 1 d is implanted. The distal end 1 d of thecatheter 1 can be open so as to define a discharge opening of thecatheter 1 that allows fluid in the lumen 7L to exit the catheter 1therethrough. The distal restrictor 2 b being positioned proximal to thedischarge opening may help prevent back flow of fluid exiting thecatheter 1 through the discharge opening. The distal restrictor 2 b canthus be positioned just proximal to the discharge opening to helpmaximize backflow prevention. The catheter's proximal end 1 p isconfigured to not be implanted and is shown outside of the patient'sbody in FIG. 1. FIG. 1 also shows a controller or motor 9 coupled to thecatheter 1 and located outside of and proximal to the catheter'sproximal end 1 p so as to not be within the catheter's shaft 7 and to belocated outside of the patient's body. Alternatively, as mentionedabove, the catheter's proximal end 1 p can be configured to beimplanted, such as when the controller or motor 9 is included in thecatheter's shaft 7.

The catheter 1 can include a pump configured to drive fluid flow throughthe catheter 1, e.g., through the lumen 7L thereof. The pump can have avariety of configurations. As in this illustrated embodiment, the pumpcan include an axial motor pump. The axial motor pump can generally beconfigured like an Archimedes' screw that drives fluid. The axial motorpump can include an impeller I and a drive shaft S (e.g., a cable or arod) each located in the catheter's shaft 7, e.g., in the lumen 7L. Alsoas in this illustrated embodiment, the impeller I can be located fullydistal to the proximal restrictor 2 a and can be located at leastpartially proximal to the second restrictor 2 b so as to be at leastpartially located within the low pressure zone and hence near the distalinlet opening. In this illustrated embodiment, the impeller I is fullylocated within the low pressure zone. The drive shaft S can extendlongitudinally through the catheter 1, e.g., through the lumen 7L, tothe controller or motor 9. The motor 9 can be configured to drive thedrive shaft S, e.g., to rotate the drive shaft S, and hence drive theimpeller I, e.g., rotate the impeller I. The drive shaft S can be asolid member, which may provide structural stability to the drive shaftS. Alternatively, the drive shaft S can be hollow, e.g., be cannulated.The drive shaft S being hollow can allow a guide wire to be advancedtherethrough, which may facilitate delivery of the catheter 1 into avein, as will be appreciated by a person skilled in the art, such as byallowing the guide wire to be introduced into a vein and the catheter 20to then be advanced over the guide wire (and into a sheath (not shown)of the system 10 advanced over the guide wire prior to the catheter 20being advanced over the guide wire, if the system 10 includes a sheath).For example, the guide wire can be introduced into the jugular vein 3(e.g., a Seldinger technique via a central venous access underultrasound guidance), and then the drive shaft S (and the catheter 1coupled thereto) can be advanced over the guide wire into the jugularvein 3.

The pump can be configured to pump fluid at a variety of rates. In anexemplary embodiment, the pump can be configured to pump fluid at a ratein a range of about 100 to 1000 ml/min, which can provide a pressurereduction in the low pressure zone from a pressure in a range of about10 to 20 mmHg (the pressure in the higher pressure zones) to a pressurein a range of about 0 to 6 mmHg (e.g., in a range of about 2 to 4 mmHg,which is a typical normal level, or in a range of about 2 to 5 mmHg,which is also a typical normal level). In at least some embodiments, thepump can have a static, e.g., unchangeable, flow rate. The flow rate canthus be predictable and/or chosen for a specific patient. In otherembodiments, the pump can have an adjustable flow rate. The flow ratebeing adjustable can help the pump accommodate changes in the patient'scondition over time and/or allow the pump to be driven at a selectedrate for a particular patient. The flow rate can be adjustable in avariety of ways, as will be appreciated by a person skilled in the art,such as by being wirelessly adjusted using a user-operated controldevice located external to the patient and configured to wirelesslycommunicate with the pump (e.g., with the controller 9) to adjust theflow rate thereof.

In at least some embodiments, the controller 9 can be configured to bein electronic communication with at least one pressure sensor (notshown). A person skilled in the art will appreciate that a variety ofsuitable sensors can be used for monitoring pressure, such as centralvenous pressure (CVP) or other fluid pressure sensors, and bloodpressure sensors. The at least one pressure sensor can be implanted inthe patient as part of the pump, implanted in the patient as a separatecomponent from the pump, or the at least one pressure sensor can belocated external to the patient, such as by being on a skin surfacethereof. If not already a part of the pump so as to be in electroniccommunication therewith, the at least one pressure sensor can beconfigured to be in electronic communication with the pump over acommunication line such as a wired line or a wireless line. In anexemplary embodiment, two pressure sensors can be implanted in thepatient. One of the pressure sensors can be implanted between the firstand second restrictors 2 a, 2 b so as to be in the low pressure zone,and the other one of the pressure sensors can be implanted in the veineither proximal to the proximal restrictor 2 a (e.g., proximal to theproximal inlet) or distal to the distal restrictor 2 b (e.g., distal tothe discharge opening) so as to be in one of the higher pressure zones.The two sensors can thus allow a pressure differential to be determinedbetween the low pressure zone and the higher pressure zone. In otherembodiments, another number of pressure sensors can be implanted in thepatient (e.g., one, three, four etc.) and/or the pressure sensor(s) canbe implanted at other locations.

The catheter 1 can include at least one lumen (not shown) configured tofacilitate use of the pressure sensor(s), for example to facilitateplacement of the pressure sensor(s) and/or to be filled with a fluidsuch as saline to allow for external pressure measurement.

In addition to or instead of the one or more pressure sensors, thecontroller 9 can be configured to be in electronic communication with atleast one other type of sensor (not shown) configured to sense aparameter other than pressure. Examples of sensors that can be used tomeasure a parameter other than pressure include radio frequencytransmitters and receivers, fluid sensors, bioimpedance sensors, heartrate sensors, breathing sensors, activity sensors, and optical sensors.Examples of the measured parameter include fluid amount (e.g., asmeasured by a fluid sensor, such as a fluid sensor placed in a lung tosense fluid amount in the lung), bioimpedance (e.g., as measured by abioimpedance sensor), heart rate (e.g., as measured by a heart ratesensor), breathing rate (e.g., as measured by a breathing sensor),patient activity level (e.g., as measured by an activity sensor), andorgan dimension (e.g., as measured by an optical sensor). The sensor canbe implanted in the patient as part of the pump, implanted in thepatient as a separate component from the pump (e.g., implanted in aninterstitial space around a lung, implanted at a junction of a rightsubclavian vein of a patient and an internal jugular vein of thepatient, implanted at a junction of a left subclavian vein of a patientand an internal jugular vein of the patient, etc.), or the sensor can belocated external to the patient, such as by being on a skin surfacethereof. If not already a part of the pump so as to be in electroniccommunication therewith, the non-pressure sensor(s) can be configured tobe in electronic communication with the pump over a communication linesuch as a wired line or a wireless line. The non-pressure sensor(s) caninclude one or more sensors. In embodiments including a plurality ofsensors, each of the sensors can be configured to measure the sameparameter as or a different parameter than any one or more of the othersensors.

The motor 9 can be included as part of the pump and can be configured tobe implanted in the patient with the pump, or, as in this illustratedembodiment, the 9 can be configured to be non-implantable. The motor 9being non-implantable can help the pump have a smaller size and/or canallow the pump to be driven by a more powerful motor since the motor 9can be larger than an implantable motor.

The controller 9 can be included as part of the pump and can beconfigured to be implanted in the patient with the pump, or, as in thisillustrated embodiment, the controller 9 can be configured to benon-implantable. The controller 9 being part of the pump can help allowthe pump to be a self-contained system, although in such a controllerrequires space in the pump, which can increase a size of the pump. Thecontroller 9 being non-implantable can help the pump have a smaller sizeand/or can allow the pump to be controlled by a more powerful processorsince the processor can be more easily upgraded than if implanted withthe pump and/or since the processor's size can be less important whenoutside the pump as opposed to inside the pump.

The controller 9 can include any type of microprocessor or centralprocessing unit (CPU), including programmable general-purpose orspecial-purpose microprocessors and/or any one of a variety ofproprietary or commercially available single or multi-processor systems.The controller 9 can be a component of a control system that includesany number of additional components, such as a memory configured to canprovide temporary storage and/or non-volatile storage; a bus system; anetwork interface configured to enable the control system to communicatewith other devices, e.g., other control systems, over a network; and aninput/output (I/O) interface configured to connect the control systemwith other electronic equipment such as I/O devices (e.g., a keyboard, amouse, a touchscreen, a monitor, etc.) configured to receive an inputfrom a user.

The controller 9 can be configured to receive user input thereto tocontrol any of a variety of aspects related to the catheter 1, such asspeed of the motor 9 and ideal range of pressure for the low pressurezone.

In at least some embodiments, the pump can be configured to change itspumping rate (e.g., from zero to a non-zero value, from a non-zero valueto zero, or from one non-zero value to another non-zero value) based onpressure measured by the at least one pressure sensor. The controller 9can be configured to effect such change in response to the sensedpressure. If the measured pressure exceeds a predetermined thresholdmaximum pressure value, the pump can be configured to increase its pumprate (e.g., increase from zero or increase from some non-zero value) inan effort to decrease the pressure. For example, if the measuredpressure within the low pressure zone is too high (e.g., is above apredetermined threshold), the pump can increase its pump rate todecrease the pressure within the low pressure zone. For another example,if the measured pressure within the low pressure zone is below apredetermined threshold, the pump can decrease its pump rate to maintainor increase the pressure within the low pressure zone. For yet anotherexample, if a measured pressure differential between the low pressurezone and the higher pressure zone is not sufficiently great (e.g., isbelow a predetermined threshold), the pump can increase its pump rate toincrease the pressure differential.

In at least some embodiments, the catheter 1 can include only onerestrictor, the proximal restrictor 2 a. A higher pressure zone can thusbe proximal to the proximal restrictor, and a low pressure zone can bedistal to the proximal restrictor. The proximal restrictor 2 apositioned proximal to (e.g., upstream) of the outflow port 4 p of thethoracic duct 4 being the only restrictor of the catheter 1, instead ofthe distal restrictor 2 b positioned distal to (e.g., downstream) of theoutflow port 4 p of the thoracic duct 4, may help prevent back flow fromthe subclavian vein 5 while providing the low pressure zone andbenefit(s) thereof.

In at least some embodiments, the catheter 1 can have a soft atraumatictip at its distal end 1 d that is tapered in a distal direction and thatis flexible. The soft atraumatic tip may facilitate smooth, safeintroduction of the catheter 1 into the vein 3. Exemplary materials fromwhich the atraumatic tip can be made include polyurethanes. The cathetermay additionally include a flexible extension similar to a guide wiretip and/or have a hydrophilic coating, each of which may furtherfacilitate smooth, safe introduction of the catheter 1 into the vein 3.

In at least some embodiments, the proximal restrictor 2 a can beconfigured to only partially occlude the vein 3 in which the catheter 1is positioned when the proximal restrictor 2 a in its activatedconfiguration. This partial occlusion may facilitate normal fluid flowthrough the vein 3 even when the proximal restrictor 2 a is in theactivated configuration. In embodiments in which the proximal restrictor2 a is configured to only partially occlude the vein 3 when in itsactivated configuration, the catheter 1 can, but need not, include theproximal inlet 8 p to facilitate fluid flow through the vein 3. Thepartial occlusion can be achieved in a variety of ways. For example, theproximal restrictor 2 a can have at least one lumen or hole formedtherethrough configured to allow fluid flow therethrough when theproximal restrictor 2 a is in the activated configuration. For anotherexample, a maximum diameter of the proximal restrictor 2 a in theactivated configuration can be less than a maximum internal diameter ofthe vein 3 in which the catheter 1 is positioned to allow fluid flowaround an exterior of the proximal restrictor 2 a.

In at least some embodiments, the catheter 1 can include at least onelumen or tube (not shown) configured to pass blood therethrough outsidethe patient's body and back into the patient. Such functionality mayallow for the monitoring of blood volume and performing hemofiltration.

In at least some embodiments, the catheter 1 can include one or moreradiopaque markers (not shown) configured to be visible using an imagingtechnique such as fluoroscopy. The one or more radiopaque markers can beon the catheter's shaft 7 at or near one or more features along theshaft 7, such as any or all of the inlet openings or any or all of therestrictors 2 a, 2 b. The one or more radiopaque markers may thusfacilitate proper positioning of the shaft 7 and/or features thereonwithin a vein. For example, prior to activation of the catheter'srestrictor(s) 2 a, 2 b, the position of the restrictor(s) 2 a, 2 bwithin the vein 3 can be verified by visualizing the one or moreradiopaque markers using an imaging system.

The first and second restrictors 2 a, 2 b are discussed with respect toFIG. 1 above as being balloons configured to inflate and deflate, butthe first and second restrictors 2 a, 2 b can have other configurations.For example, the first and second restrictors 2 a, 2 b can each includea stent configured to expand (corresponding to an activatedconfiguration) and constrict (corresponding to a relaxed configuration).The expandable/constrictable stents can have a variety ofconfigurations, as will be appreciated by a person skilled in the art.Further details related to an indwelling catheter are described in U.S.application Ser. No. 15/150,637 entitled “Systems and Methods forReducing Pressure at an Outflow of a Duct,” filed May 10, 2016.

In some embodiments, a catheter can include an integral pump that canpump blood from the external volume between restrictions of the catheterinto catheter's conduit. The pump can be associated with a motor (whichcan be similar to the motor 9 in FIG. 1) that can be configured to benon-implantable such that it is disposed outside of the patient. Thepump motor can be coupled to an impeller (which can also be referred toas pump rotor) via a drive shaft, as discussed above. The motor beingnon-implantable can help the pump have a smaller size and/or can allowthe pump to be driven by a more powerful motor since the motor can belarger than an implantable motor. Furthermore, in some embodiments, themotor can be included as part of the pump and can be configured to beimplanted in the patient with the pump.

The catheter also includes first and second restrictors each configuredto at least partially occlude the vein within which the catheter isimplanted and thus to restrict fluid flow within the vein when therestrictors are activated. The restrictors can each be configured tomove between an activated configuration in which the restrictor occludesthe vein, and a relaxed configuration in which the restrictor does notocclude the vein. The restrictors can each be in the relaxedconfiguration during implantation of the catheter to ease introductionof the catheter into the patient's body and into the vein. Each of therestrictors can include a balloon configured to be inflated, where inthe relaxed configuration the balloon is not inflated and in theactivated configuration the balloon is inflated.

The impeller can be disposed at various locations within the catheter.For example, FIG. 2 illustrates schematically an example of a catheter200, having proximal and distal ends 200 p, 200 d, that has first andsecond restrictors 202 a, 202 b and an impeller 210 positionedproximally of the first restrictor 202 a. In this example, the firstrestrictor 202 a is a proximal restrictor and the second restrictor 202b is a distal restrictor. The first and second restrictors 202 a, 202 bcan be in the form of expandable elements such as balloons and are shownin FIG. 2 in an activated, inflated configuration in which they occludethe vein. The catheter 200 also has an atraumatic tip 204 thatfacilitates placement of the catheter into the vein of the patient, acatheter shaft 206 having an inlet tube 213 extending therethrough, aconduit 208, inlet opening 212 and two opposed outlet openings 214 a,214 b formed in the wall of the catheter 200. The impeller 210 can becoupled to a motor (not shown) via a drive shaft 216. The components ofthe catheter 200 can be similar to the components of the catheter 1(FIG. 1) and are therefore not described in detail.

FIG. 3 illustrates schematically another embodiment of a catheter 300 inaccordance with the described techniques having an impeller positionedbetween first and second restrictors. As shown in FIG. 3, a catheter300, having proximal and distal ends 300 p, 300 d, has first and secondrestrictors 302 a, 302 b and an impeller 310 positioned between thefirst and second restrictors 302 a, 302 b. In this example, the firstrestrictor 302 a is a proximal restrictor and the second restrictor 302b is a distal restrictor. The first and second restrictors 302 a, 302 bcan be in the form of expandable elements such as balloons and are shownin FIG. 3 in an activated, inflated configuration in which they occludethe vein. Similar to the catheter 200 in FIG. 2, the catheter 300 has anatraumatic tip 304, a catheter shaft 306 having an inlet tube 313extending therethrough, a conduit 308, and inlet and outlet openings312, 314. In some embodiments, the outlet opening 314 can be in the formof two opposed openings formed in the wall of the inlet tube 313.

The impeller 310 can be coupled to a motor (not shown) via a drive shaft316. As shown in FIG. 3, the impeller 310 and at least a portion of thedrive shaft 316 (which is shown partially) are disposed in an enlargedportion 315 of the inlet tube 313. The components of the catheter 300can be similar to the components of the catheter 1 (FIG. 1) and aretherefore not described in detail.

FIG. 4 illustrates schematically another embodiment of a catheter inaccordance with the described techniques having an impeller positioneddistally of a distal (or “second) restrictor. Thus, as shown in FIG. 4,a catheter 400, having proximal and distal ends 400 p, 400 d, has first(proximal) and second (distal) restrictors 402 a, 402 b. The first andsecond restrictors 402 a, 402 b can be in the form of expandableelements such as balloons and are shown in FIG. 4 in an activated,inflated configuration in which they occlude the vein. The catheter 400has an impeller 410 positioned distally of the distal restrictor 402 b.Similar to the catheter 200 in FIG. 2, the catheter 400 has anatraumatic tip 404, a catheter shaft 406 having an inlet tube 413extending therethrough, a conduit 408, an inlet opening 412 and twoopposed outlet openings 414 a, 414 b. As shown in FIG. 4, the impeller410 is coupled to a motor 409 via a drive shaft 416. In thisimplementation, the motor 409 is disposed within an enlarged portion ofthe catheter's tip 404, as shown in FIG. 4.

In the examples shown in FIGS. 2, 3 and 4, an inlet opening of the pumpcan be within a tube or it can be formed to extent inwards from radialopenings. The outlet opening of the pump can be formed into a tube or itcan be formed to extend outward via radial openings. Any of thecatheters 200, 300, and 400 can include one or more sensors positionedat desired locations. For example, at least one pressure sensor can bedisposed between the restrictors and can monitor the lymphatic outletpressure. The pump can be an implantable pump. The motor configured tooperate the impeller can include or can be associated with a controller.The controller can control various operating parameters of the impeller,such as its speed. The lymphatic outlet pressure as well as the motorcurrent and voltage consumption can be used as inputs to the motorcontroller.

In some embodiments, the pump inlet tube can be expandable to handlemore fluid (e.g., from the thoracic duct) and to reduce flow resistance.The expandable segment can extend between the inlet tube opening and theimpeller. FIG. 5 illustrates schematically another embodiment of acatheter 500 in accordance with the described techniques having animpeller positioned proximally of a proximal restrictor and having anexpandable inlet tube segment extending between the inlet tube openingand the impeller.

As shown in FIG. 5, the catheter 500, having proximal and distal ends500 p, 500 d, has first (proximal) and second (distal) restrictors 502a, 502 b and an impeller 510 positioned proximally of the proximalrestrictor 502 a. The first and second restrictors 502 a, 502 b can bein the form of expandable elements, such as, e.g., balloons, that areshown in FIG. 5 in an activated, inflated configuration in which theyocclude the vein. The catheter 500 has an atraumatic tip 504, a cathetershaft 506 having an inlet tube 513 extending therethrough, a conduit508, an inlet opening 512 and two opposed outlet openings 514 a, 514 b.As shown, the inlet tube 513 has an expanded portion 515 extendingbetween the inlet tube opening 512 and the impeller 510.

The impeller 510 can be coupled to a motor (not shown) via a drive shaft516. The components of the catheter 500 can be similar to the componentsof the catheter 1 (FIG. 1) and are therefore not described in detail.

The catheters 200, 300, 400, and 500 can be disposed within thepatient's body to alleviate fluid overload similar to the manner inwhich catheter 1 (FIG. 1) is shown to be disposed within the patient'sbody. However, it should be appreciated that the catheters 200, 300,400, and 500 can be disposed in the patient's body in other ways.

In some embodiments, a single restrictor can be used. The restrictor canbe positioned, for example, in the left innominate vein so the bloodpressure above the restrictor is reduced by pumping the blood downstreaminto the innominate vein. FIG. 6 illustrates schematically anotherembodiment of a catheter 600 in accordance with the described techniqueshaving one restrictor 602 and an impeller 610 positioned proximally ofthe restrictor 602. The restrictor 602 can be in the form of anexpandable element, such as, e.g., balloon that is shown in FIG. 6 in anactivated, inflated configuration in which it occludes the vein.

As shown in FIG. 6, the catheter 600, having proximal and distal ends600 p, 600 d, has an atraumatic tip 604, a catheter shaft such as aninlet tube 613, an inlet opening 612 and an outlet opening 614. Theimpeller 610 can be coupled to a motor (not shown) via a drive shaft616. As shown, the impeller 610 is disposed in proximity to the inletopening 612, to cause the blood to enter the catheter shaft. As alsoshown in FIG. 6, the restrictor 602 is a compliant restrictor that isdisposed around the catheter shaft in a manner that allows the blood toflow therethrough. The impeller 610 is configured to pump fluid throughthe catheter shaft regardless of whether the restrictor 602 is in theactivated configuration or the relaxed configuration. However, thecatheter 600 is configured to lower the pressure at the thoracic ductoutlet only when the restrictor 602 is in the activated configuration(e.g., inflated) and when the impeller 610 is operating.

It should be appreciated that the indwelling catheters 200, 300, 400,500, and 600 are shown by way of example only. It should also beappreciated that these catheters can have other components not shownherein. For example, as mentioned above, any of the catheters can haveone or more sensors of various types. Any of the catheters 200, 300,400, 500, and 600 can include at least one inflation lumen through whichan inflation fluid (e.g., air, liquid, etc.) can be introduced toinflate/deflate the restrictors. The catheters can be delivered to atreatment site using a sheath configured to be at least partiallyimplantable within a patient's vein, the sheath having a lumen extendingtherethrough. The catheter shaft can be movably positioned within andextending through the lumen of the sheath, and the catheter shaft can beconfigured to be at least partially implantable within a patient's vein.Thus, the catheters described herein can be part of an indwellingcatheter system configured for at least partial placement within a veinof a patient.

In some embodiments, various systems and methods are provided forreducing pressure at an outflow of a duct such as the thoracic duct orthe lymphatic duct, for example, the right lymphatic duct. An indwellingcatheter can be configured to be at least partially implanted within avein of a patient in the vicinity of an outflow port of a duct of thelymphatic system. The catheter can include a drive shaft operativelycoupled to an impeller, a first selectively deployable restrictionmember adjacent and proximal to the impeller and having a membrane, anda second selectively deployable restriction member proximal to the firstrestriction member. The second restriction member is operatively coupledto a flow regulation component configured to direct a controlled volumeof fluid from an upstream side of the second restriction member to adownstream side of the second restriction member. A motor can beconfigured to rotate the drive shaft and the impeller.

In some embodiments, various systems and methods are provided forreducing pressure at an outflow of a duct such as the thoracic duct orthe lymphatic duct, for example, the right lymphatic duct. In general,the systems and methods may be effective to reduce edema conditions,such as fluid overload, in a patient by lowering an outflow pressure ina region around the patient's thoracic/lymphatic duct outflow. As aresult of lowering the outflow pressure at the thoracic and/or lymphaticducts, higher lymphatic return will be achieved, enabling the lymphaticvessel flow to be at or near normal levels. The systems and methods maybe effective to rapidly alleviate conditions of the edema and increasethe patient response rate. In an exemplary embodiment, the systems andmethods may be particularly useful to treat acute fluid overload,however a person skilled in the art will appreciate that the systems andmethods can be used in various procedures for treating a lymphaticsystem fluid clearance imbalance.

In one embodiment, an indwelling catheter can be configured to be atleast partially implanted (e.g., partially implanted or fully implanted)within a vein of a patient in the vicinity of an outflow port of a ductof the lymphatic system, e.g., in the vicinity of an outflow port of thethoracic duct or in the vicinity of an outflow port of the lymphaticduct, for example, the right lymphatic duct. Exemplary materials fromwhich the catheter can be made include polyurethanes. The catheter caninclude first and second restrictors (also referred to herein as“restriction members”), at least one of which is configured to at leastpartially occlude the vein within which the catheter is implanted andthus to restrict fluid flow within the vein when the restrictors areactivated. The restrictors can each be configured to move between anactivated configuration, in which the restrictor occludes the vein, anda relaxed configuration, in which the restrictor does not occlude thevein. The restrictors can each be in the relaxed configuration duringimplantation of the catheter to ease introduction of the catheter intothe patient's body and into the vein. Each of the restrictors caninclude a balloon configured to be inflated (such that the balloonexpands radially) where in the relaxed configuration the balloon is notinflated and in the activated configuration in which the balloon isinflated. The balloon can be, for example, a doughnut-shaped. Therestrictors can be configured to be inflated to expand to the same ordifferent diameters. Also, in some embodiments, the restrictors can haveinner lumens of different diameters.

The restrictors can be made from any one or more of a variety ofmaterials configured to expand upon the delivery of a fluid thereto andto contract upon the withdrawal of the fluid. Exemplary materials fromwhich the balloon can be made include polymeric materials such as PEBAX,silicones, polyurethanes, and nylons. The catheter can include at leastone inflation lumen through which an inflation fluid (e.g., air, liquid,etc.) can be introduced to inflate/deflate the restrictors. The at leastone inflation lumen can include one lumen in fluid communication withboth of the restrictors such that the restrictors can be simultaneouslyinflated/deflated, or can include first and second lumens with the firstlumen in fluid communication with the first restrictor and the secondlumen in fluid communication with the second restrictor such that therestrictors can be selectively inflated simultaneously or sequentially.The catheter can include a pump, such as an axial motor pump, configuredto pump fluid through the catheter. The catheter can be coupled to amotor configured to drive the pump. The motor can be included in thecatheter (e.g., within a shaft of the catheter) and be configured to beimplanted with the catheter, or the motor can be located outside of thecatheter (e.g., outside of the catheter's shaft) and be configured to belocated outside of the patient rather than be implanted therein.

In one embodiment of using the catheter, the catheter can be positionedat a desired location within the vein. The first and second restrictorscan then each be activated (simultaneously or sequentially) to move fromthe relaxed configuration to the activated configuration. The first andthe second restrictors, when activated so as to provide, in combinationwith other components, occlusion within the vein, define a low pressurezone therebetween within a portion of the vein in which the catheter ispositioned. Higher pressure zones accordingly exist on either side ofthe restrictors. The motor can drive an impeller to induce the lowpressure zone by causing fluid to be pumped through the catheter. Thecatheter and the restrictors can be positioned within the vein such thatthe low pressure zone is adjacent to an outflow port of a duct (e.g.,the thoracic duct or the lymphatic duct, such as, for example, the rightlymphatic duct) to allow fluid to pass from the lymph duct outflow portto the portion of the catheter housed within the vein so that fluid canflow out of the catheter.

In at least some embodiments, at least one of the restrictors of acatheter can be inflated and deflated from time to time to enable freeflow of blood in a patient's vein in which the restrictor(s) arepositioned and thus enable the system to stop working for a period oftime. This period of time can be required in such treatments to allowfor the assessment of the patient's clinical condition, allow thepatient to undergo other treatments or enable him to go to the bathroomand/or to wash any stagnation points that might have occurred. Therestrictors can be configured and operated as described, for example, inU.S. application Ser. No. 14/625,930 entitled “System And Method ForTreating Pulmonary Edema,” filed Feb. 19, 2015, and in U.S. applicationSer. No. 14/726,715 entitled “Systems and Methods for Treating PulmonaryEdema,” filed Jun. 1, 2015, the content of each of which is incorporatedby reference herein in its entirety. In addition, some features of thecatheter system described herein can be implemented as described in U.S.App. Publ. No. 2016/0331378 entitled “Systems and Methods for ReducingPressure at an Outflow of a Duct,” filed May 10, 2016, the content ofwhich is incorporated by reference herein in its entirety

In some embodiments, the catheters described herein can be configured tobe placed in a patient's body for up to about seventy-two hours, e.g.,the catheter can be indwelled in the body for up to about seventy-twohours. The catheter systems are configured to be able to be accuratelyfixated and deployed in a patient's body. The systems can be configuredto be conveniently placed to a desired location in a patient (torque canbe applied), and they possess compatibility with a guide wire andsheath, ability to overcome leads and leads effects, ability toautomatically maintain a working point for 72 hours (<5 mmHg at theisolated zone), and ability to measure pressure at the pressurereduction zone. It should be appreciated, however, that in otherinstances a catheter system in accordance with the described techniquescan be indwelled in the body for a duration of time greater thanseventy-two hours. The system can be configured to maintain hemostasis.

A person skilled in the art will appreciate that the systems and methodsdisclosed herein can be used with a variety of surgical devices,including measuring devices, sensing devices, locator devices, insertiondevices, etc.

In some embodiments, a catheter system is provided that can locallyreduce pressure at an outflow of a lymphatic duct and to thus enhancelymphatic drainage, without affecting the intravascular systemic bloodpressure.

FIG. 7 illustrates one example of a catheter system in accordance withthe described techniques. The catheter system includes an indwellingcatheter, which can be in the form of a disposable catheter unit, and amechanical fixator part which can be enclosed in a sterile package priorto use. Some components of the system, such as a console having acontroller, a display configured to display information and receive userinput, cables, etc., can be reusable components. As shown in FIG. 7, thesystem includes a main catheter tube or shaft, a distal assembly, acentralizer member, and a proximal assembly. The main catheter shaft iscoupled to a propulsion system including at least an impeller and amotor (which can be disposed at least in part outside of the patient'sbody), a distal restriction member in the form of a distal balloon, anda distal atraumatic tip.

The centralizer member can be in the form of a housing encompassing asealing component and at least a part of a motor. The housing isconfigured to keep the assemblies of the system aligned, while allowingan axial movement of the assemblies. The system includes a motorconfigured to move a drive shaft (e.g., a torque coiled drive shaft or ashaft having another configuration) inside a multi-lumen sleeve. Inaddition, the motor is configured to cause the distal balloon toinflate. One or more components of the motor can be disposed within thecentralizer member. The motor can be, for example, an extracorporealmotor configured to deliver the driving force to the impeller throughthe drive shaft. The motor can have a shaft with a channel extendingtherethrough to allow a guide wire to be inserted through the shaft.Additionally or alternatively, a mechanism configured to facilitateinsertion and removal of the guide wire can be utilized. The cathetercan include at least one inflation lumen through which an inflationfluid (e.g., air, liquid, etc.) can be introduced to inflate/deflate therestrictors. The restrictors can be inflate/deflate using separatecomponents. The catheter can also include a suction lumen, and any otherlumens.

The proximal assembly includes a proximal assembly tube having aproximal restriction member in the form of a proximal balloon at adistal end thereof. The proximal assembly is configured to regulateblood flow in the jugular vein. The proximal assembly can include aregulation mechanism configured to adjust the central venous pressure(CVP).

FIGS. 7, 8, 9A, and 9B show one embodiment of an implantable cathetersystem 700 including a catheter shaft or tube 702 (which can also bereferred to as a “main catheter”) having a drive shaft 703 extendingtherethrough, a centralizer 704, a sheath 706 disposed proximally to thecentralizer 704 and having the catheter tube 702 extending therethroughin a lumen thereof, and a distal tip 708. As also shown, the cathetersystem 700 includes distal and proximal restrictors 712, 714 disposedover the catheter tube 702. In the illustrated embodiment, the distaland proximal restrictors 712, 714 include radially expandable balloons,such as, for example, doughnut-shaped balloons. The distal tip 708 canbe a distally tapered atraumatic element that facilitates insertion ofthe catheter system 700 into an implantation site (e.g., a vein). Insome embodiments, the catheter system 700 can be fully cannulated suchthat a guide wire can be inserted through the entire system, includingthe distal tip 708.

Each of the distal and proximal restrictors 712, 714 has a lumenextending therethrough that receives the catheter tube 702 and allowsthe blood to pass through the lumen. In some embodiments, a diameter ofthe distal restrictor 712 can be greater than a diameter of the proximalrestrictor 714, and a diameter of the inner lumen of the distalrestrictor 712 is greater than a diameter of the inner lumen of proximalrestrictor 714. In this way, whereas the proximal restrictor 714 reducesa blood flow that passes therethrough, the distal restrictor 712 allowsa larger volume of the blood to flow therethrough. In other embodiments,the restrictors 712, 714 can be configured to be inflated to the same orsimilar diameter, whereas the distal restrictor 712 can be inflated asto become of a larger diameter than the inflated proximal restrictor714. Also, in some implementations, the distal and proximal restrictorscan have approximately the same diameter in the activated (e.g.,inflated) configuration.

In some embodiments, when at least a portion of the system 700 isimplanted in the patient's body and the restrictors 712, 714 areactivated (or deployed), the blood passes from a proximal side of theproximal restrictor, into a zone between the restrictors, and into andthrough the distal restrictor, as discussed in more detail below. Inthis way, a low pressure zone is created between the distal and proximalrestrictors 712, 714.

As shown in FIG. 8, a proximal assembly 710 encompasses a sleeve orproximal assembly tube 720 having a first sealing component 722 at aproximal end thereof and the proximal restrictor 714 at a distal endthereof. The catheter system 700 also includes the sheath 706 that has aportion of the proximal assembly tube 720 extending therethrough, and asecond sealing component 724. In the assembled configuration, as shownin FIG. 7, the sheath 706 is disposed over the proximal assembly tube720 such that a distal end 706 d of the sheath 706 is proximal to theproximal restrictor 714. In this embodiment, an impeller assembly 705 isdisposed distal to the distal restrictor 712.

As shown in FIGS. 7, 8, 9A, and 9B, a distal end of the drive shaft 703is attached to the impeller assembly 705 that includes an impeller 715(also shown in FIG. 15) and an impeller cage or housing 730 (also shownin FIG. 16) disposed around the impeller 715 and having openings 732(e.g., radial openings) that allow blood to flow therefrom. The membrane716 is, in this embodiment, a conical, distally tapered element coupledto the distal restrictor 712. The membrane 716 can define an enclosedtunnel or lumen in fluid communication with an inner lumen of theimpeller housing 730 seating the impeller 715. In this way, the membrane716 directs the fluid from the distal restrictor 712 towards theimpeller 715. The distally-tapered configuration of the membrane 716provides reduced resistance to a blood flow, thus enabling the impeller715 to rotate as a lower speed that would otherwise be required to pumpthe blood at the same rate.

For example, the membrane 716 can at least partially wrap around thedistal restrictor 712 or be otherwise coupled to the distal restrictor712 to as to direct distally the blood flow that passes from a proximalto distal side of the distal restrictor 712. As shown in FIG. 9A, adistal portion 716 d of the membrane 716 is attached to the impellerhousing 730. For example, the distal portion 716 d of the membrane 716can at least partially wrap around a proximal end of the impellerhousing 730. In this way, the blood flowing from a proximal side of thedistal restrictor 712 passes through an inner lumen of the distalrestrictor 712 and is directed by the membrane 716 into a tunnel orlumen of the impeller housing 730 with the impeller 715 therein. As theimpeller 715 rotates, the blood (which can include other fluids) isdirected from the lumen of the impeller housing 730 to the outside ofthe housing 730 into the vein, through openings formed in the wall ofthe housing 730.

In this example, as shown in FIGS. 7 and 8, the sheath 706 includes atleast one fixture 734 configured to removably couple the catheter system700 to a patient (e.g., to the patient's skin). The fixture 734 can haveany suitable configuration. The sheath 706 can also have components thatcover and protect the sheath 706 during deployment of the cathetersystem 700. In the illustrated embodiment, the sheath 706 is disposed soas to encompass at least a portion of the proximal assembly 710 suchthat the proximal restrictor 714 is disposed distally to the distal end706 d of the sheath 706.

As shown in FIG. 7, the drive shaft 703 extends at least partiallythrough the proximal assembly tube 720, and the centralizer 704encompasses at least a portion of the proximal assembly 710. The driveshaft 703 is coupled at a proximal end thereof to a motor 740 configuredto operate to cause the drive shaft 703 to rotate, which causes theimpeller 715 to also rotate. The motor 740 can have any suitableconfiguration and it can be positioned outside of the patient's bodywhen the system 700 is at least partially implanted into the patient'sbody. In some implementations, the motor 740 can be positioned adjacentto the patient's body, in the vicinity of the incision made to insertthe catheter into the patient's body. Additionally, the motor 740 can bedetachable from the drive shaft 703 such that the motor 740 isreleasably and replaceably coupled to the drive shaft 703. Thus, themotor can be reusable. Furthermore, in some implementations, the motorcan be implantable, in which case it may or may not be associated withan implantable power source.

As shown schematically in FIG. 7, the catheter system 700 can be coupledto a controller device 725 configured to control operation of the motor740. For example, the controller device 725 can receive information(e.g., fluid pressure measurements) acquired by sensor(s) associatedwith the catheter system 700 and the controller device 725 can controloperation of the motor 740 (e.g., increase or decrease motor RPM) basedon the monitored blood pressure. The motor 740 can be controlled suchthat operation of the system attains a certain desired blood pressure ina certain area in the patient's body, e.g., at an outflow port of alymphatic duct, such as a right lymphatic duct. The motor 740 can becontrolled using any suitable mechanism(s). For example, a closedcircuit control mechanism can be used to adjust a speed of rotation ofone or more components of the motor 740, to thereby control the speed ofthe impeller 715. The control mechanism can operate such that the motor740 is cause to increase its RPM to thereby lower a pressure in the lowpressure zone. The pressure in the low pressure zone can be monitoredusing one or more suitable pressure sensors.

FIGS. 9A and 9B show the distal assembly 718 that includes the impellerassembly 705 having the impeller 715 that is driven by a motor (e.g., amotor 740 of FIG. 22) to which the impeller 715 is coupled via the driveshaft 703. As shown in FIG. 9B (and also shown in FIG. 19), therestrictor 712 has an inner lumen 717 that is configured to allow fluid(e.g., blood) to pass therethrough. An outer portion 721 of therestrictor 712 surrounding the lumen 717 is selectively deployable(e.g., inflatable), and the outer portion can be coupled to an inflationlumen configured to cause the outer portion 721 to inflate. The outerportion 721 can be in the form of a compliant balloon, and the innerlumen 717 can be formed when the balloon is inflated. Furthermore, insome embodiments, the inner lumen can be defined by a separate tubularstructure having the outer portion 721 coupled circumferentiallythereto.

FIG. 10A illustrates a portion of the proximal assembly 710. As shown, adistal end 720 d of the proximal assembly tube 720 can include or can becoupled to a flow regulator component 736. As shown in FIG. 10A, theflow regulator component 736, which is disposed proximally to theproximal restrictor 714, includes opening sections or openings 738 thatallow a blood flow (e.g., a jugular blood flow) to enter through theopenings 738. The flow regulator component 736 can include one or more(e.g., four) openings, though it should be appreciated that any suitablenumber of openings can be formed. In at least some embodiments, once theimplantable catheter system 700 is implanted in the patient's body andthe restrictors 712, 714 are activated, the proximal assembly 710 canregulate the jugular flow and pressure to create a low pressure zonebetween the restrictors 712, 714. In particular, once the impeller 815is activated, the jugular flow is caused to enter through the openings738 of the flow regulator component 736 and into a gap 719 (markedschematically in FIG. 10A) between an outer wall of the catheter tube702 and an inner wall of the proximal restrictor 714 defining an innerlumen (not shown) of the proximal restrictor 714. The volume of thejugular flow is thus reduced. In at least some embodiments, the jugularflow in the range from about 100 ml/min to about 600 ml/min enters thegap 719. In the illustrated embodiments, the proximal restrictor 714 hasthe inner lumen that can be similar to a lumen of the distal restrictor,such as, e.g., lumen 717 in FIG. 19. A diameter of the proximalrestrictor's lumen can be smaller than a diameter of the inner lumen ofthe distal restrictor, as shown in FIGS. 7 and 8. The proximalrestrictor 714 of the proximal assembly 710 can be in the form of aballoon of a suitable size. In at least some embodiments, the balloon'sdiameter is from about 10 mm to about 25 mm, though it should beappreciated that the balloon can have any suitable diameter.

FIG. 10B shows an example of a cross-section of the proximal assembly710 taken at the flow regulator component 736. The flow regulatorcomponent 736 can be part of the distal end of the proximal assemblytube 720 (FIG. 8). As shown in FIG. 10B, the proximal assembly 710includes an inflation lumen 742 that assists in inflation of theproximal restrictor 714. In at least some embodiments, a diameter of theinflation lumen 742 is from about 0.2 mm to about 0.6 mm, though itshould be appreciated that the inflation lumen 742 can have any suitablediameter. The proximal assembly 710 can have associated therewith (e.g.,coupled thereto in a suitable manner) one or more pressure sensor(s)that are configured to acquire pressure measurements at the jugularand/or subclavian veins. In pathological conditions such as, forexample, ADHF, the central venous pressure (CVP) can be about 15 mmHgand, in some cases, it can vary from about 10 mmHg to about 40 mmHg.When the patient has decongested, the pressure during inspiration can belower—e.g., about −10 mmHg; and when the patient is congested andperforms, for example, a Valsalva maneuver, the pressure can behigher—e.g., about 40 mmHg. The low pressure zone reduces the CVPlocally at the site of the thoracic duct outflow to normal levels, suchas in a range from about 2 mmHg to about 6 mmHg. In some embodiments,including any of the embodiments described herein in connection with anyof catheter systems, the pressure of about 5 mmHg is maintained in thelow pressure zone. As shown in FIG. 10B, the inflation lumen 742 canhave one or more separate lumens 744 formed therein, which can be, forexample, an inflation lumen in fluid (or air, or other gas)communication with the restrictors and configured to cause therestrictors to be activated, and a control lumen including one or morepressure sensors. The inflation lumen 742 can include any other lumens.Additionally, in some embodiments, the inflation lumen 742 can includeports that allow flushing the lumen 742.

FIGS. 13-22 illustrate examples of various components of the cathetersystem 700. Thus, FIG. 13, illustrating the catheter shaft or tube 702in cross-section, shows that the catheter tube 702 includes an innerlumen 746 configured to hold the drive shaft 703. The inner lumen 746 ofthe catheter tube 702 can also include one or more inflation lumens 748.The lumen 746 can include any other lumens. The catheter tube 702 canhave associated therewith (e.g., coupled thereto in a suitable manner)one or more pressure sensor(s) that are configured to acquire pressuremeasurements at the jugular and/or subclavian veins. The pressure can beabout 15 mmHg and, in at least some embodiments, it can vary from about10 mmHg to about 40 mmHg. When the patient has decongested blood flow,the pressure during inspiration can be lower—e.g., about 10 mmHg; andwhen the patient is congested and performs, for example, a Valsalvamaneuver, the pressure can be higher—e.g., about 40 mmHg. The cathetertube 702 can have various configurations. In some embodiments, thecatheter tube 702 can be flexible such that it can bend, if required.For example, in at least some embodiments, the catheter tube 702 isresiliently bendable.

FIG. 14 illustrates one embodiment of a cross-section of the drive shaft703. As shown, the drive shaft 703 has an inner limner 750 extendingtherethrough that can receive a guidewire therein. The drive shaft 703can be in any suitable form—for example, in at least some embodiments,it can be in the form of a torque coil cable having a lumen extendingtherethrough. In some embodiments, the drive shaft can be associatedwith a sleeve that is configured to house the drive shaft so as toreduce friction and influence of heat and wear.

FIG. 15 shows the impeller assembly 705 including the impeller 715. Theimpeller 715 can have various configurations, and it should beappreciated that the impeller 715 is shown in FIG. 15 by way of exampleonly. The impeller 715 is configured to operate to pump fluid, such asblood, outwards from a center of rotation. For example, the impeller 715can pump blood from a center portion of the catheter system 700 tothereby drive the blood distally and outward towards a perimeter of thevessel in which the catheter system 700 is implanted. In thisembodiment, as shown in FIG. 15, the impeller 715 is in the form of arotatable component having one or more semi-spiral blades 754 extendingaxially along an impeller shaft or body 752 that extends along alongitudinal axis of the draft shaft 703. The impeller body 752 can becoupled to the distal end of the draft shaft 703 in any suitable manner.As shown in FIG. 15, the spiral blades 754 are wound around the impellerbody 752 such that the impeller 715 has generally a bow-like shape asviewed along the longitudinal axis of the draft shaft 703. In someembodiments, the impeller 715 can have more than one (e.g., two, three,four, or greater than four) blades 754 extending from the impeller body752. The impeller body 752 includes an inner lumen (not shown) extendingtherethrough that is configured to receive a guide wire therethrough. Itshould be appreciated that the impeller 715 can have any otherconfigurations, including a configuration having one blade wound arounda shaft in a spiral-like manner, a configuration having any type ofsemi-spiral or spiral blades, etc.

The impeller 715 can have any suitable dimensions. For example, in someembodiments, a diameter of the largest area of the impeller 715, asmeasured in a plane perpendicular to the longitudinal axis of the driveshaft 703, can range from about 3 mm to about 5 mm. A length of theimpeller 715 can range from about 4 mm to about 8 mm. It should beappreciated, however, that the impeller can have any other suitabledimensions, as the described embodiments are not limited in thisrespect. Also, the impeller can have any suitable configuration and itcan be part of any suitable pump. Regardless of its specificconfiguration, the impeller 715 is driven via a suitable motor thatrotates the drive shaft 703 having the impeller 715 coupled to thedistal end thereof. In some embodiments, the impeller can be driven to arotation speed of less than about 25000 RPM (revolutions per minute). Insome embodiments, the operation of the impeller causes the blood to flowat a rate of about 800 ml/min, and the pressure gradient is about 20mmHg. The rotational speed can be selected to reduce hemolysis risk.

As mentioned above, FIG. 16 illustrates the impeller housing or cage730. The impeller housing 730 that also house a bearing system.Regardless of its specific configuration, the impeller housing 730 isconfigured so as to pass blood from its proximal end to a distal end.The blood is passed through the openings 732. The impeller housing 730can have any suitable dimensions. In some embodiments, the impellerhousing dimensions follow impeller dimensions, such that only a smallgap (e.g., 0.05 mm-0.2 mm) exists between the impeller (e.g., an outersurface of widest portion(s) of the impeller such as, e.g., impeller 715of FIG. 15), and the impeller housing 730.

FIG. 17 illustrates an alternative embodiment of an impeller housing730′ of an indwelling catheter system. In this example, the impellerhousing 730′ includes an extension 731 configured to support thecatheter while keeping a suction lumen of the distal restrictor fullyopen.

FIG. 18 illustrates a membrane 756 (e.g., membrane 716 shown in FIGS. 7and 8).

In this example, the membrane 716 is a conical membrane, though it canhave other configurations. The conical membrane can allow diffusing theblood flow from an isolated zone to the impeller. The conical shapefacilitates delivering the flow smoothly to the impeller, which reducesresistance to the flow. The membrane 756 can have any suitabledimensions. For example, in at least one embodiment, a portion L1 of themembrane 756 having a conical shape, shown in FIG. 18, can have a lengthin a range from about 2 mm to about 10 mm.

FIG. 19 shows the distal restrictor 712 that is, in the illustratedembodiments, is generally doughnut-shape having an inner lumen 717 thatallows for passage of fluid therethrough. As shown, the distalrestrictor 712 has a holder 713 (also shown in FIG. 20) coupled thereto.In this example, the holder 713 is in the form of a “Mercedes-wheel”shaped holder. As shown in FIGS. 19 and 20, the holder 713 has anopening 723 configured to hold the catheter tube 702 and the drive shaft703 received within the catheter tube. The outer portion 721 of therestrictor 712 surrounding the lumen 717 is selectively deployable(e.g., inflatable), and the outer portion can be coupled to a deploymentor inflation lumen configured to cause the outer portion 721 to inflate.This configuration of the holder 713 allows holding the drive shaft 703centralized and also keeps the impeller 715 in place. The distalrestrictor 712 can have any suitable size. In at least one embodiment, adiameter of the restrictor, in the deployed (inflated) configuration isin a range from about 14 mm to about 30 mm. Although not shown in FIG.19, in the illustrated embodiments, the distal restrictor 712 has amembrane coupled thereto that directs a fluid flow towards the impeller.In addition, a proximal restrictor can be configured in a similarmanner.

FIG. 21 shows a distal tip 708 of the catheter system 700, which can bean atraumatic tip that allows a gentle insertion of the catheter system700 into a vessel in a patient's body. The distal tip 708 can have aninner lumen 760 extending therethrough that is configured to receive aguide wire therein. The distal tip 708 can have its proximal end coupledto an impeller housing—e.g., any of the housings 730 (FIG. 16), 730′(FIG. 17), or the impeller housing having any other configuration. Thedistal tip 708 can have any suitable dimensions. For example, in someembodiments, a length of the distal tip 708 can vary in a range fromabout 10 mm to about 30 mm.

FIG. 22 illustrates one embodiment of a motor 740′ which is configuredto deliver a driving force to the impeller through the drive shaft. Themotor 740′ (e.g., motor 740 of FIG. 7) can be, for example, anextracorporeal motor. However, it should be appreciated that, in someimplementations, the motor 740′ can be implantable. In some embodiments,a shaft of the motor 740′ that is configured to be driven and to causethe rotation of the drive shaft. The motor shaft can have a lumenextending therethrough (not shown) that can receive therein a guidewire. In some embodiments, the motor shaft is associated with amechanism configured to assist in insertion and removal of the guidewire from the motor shaft's lumen. The motor 740′ can have any suitabledimensions. In some embodiments, a diameter of the motor 740′ can varyin a range from about 4 mm to about 30 mm, and a length of the motor740′ can vary in a range from about 10 mm to about 50 mm. It should beappreciated that the components that can be included in the cathetersystem 700, or other catheter systems in accordance with the describedsubject matter, are shown in FIGS. 13 to 22 by way of example only, andthat the dimensions of the components are also shown by way of exampleonly.

Referring back to FIGS. 11 and 12, FIG. 11 illustrates an embodiment ofa catheter system 800 for treating edema with a straight multi-lumenconfiguration implanted in a patient's body. FIG. 12 shows a similarcatheter system 900 implanted in a patient's body, the system 900 havinga bent or kink 901 of a catheter tube between proximal and distalrestrictors. The systems 800, 900 can have any of the componentsillustrated in connection with FIGS. 7 to 10B and FIGS. 13 to 22. Itshould be noted that the thoracic duct is not shown in FIGS. 11 and 12.In this example, each of the systems 800, 900, as well as other cathetersystems described herein, can be implanted in the patient such that thedistal restriction member is disposed in the innominate vein, and theproximal restriction member is disposed in the jugular vein, e.g., at adistance of about 1.5 cm from the bifurcation of the jugular andsubclavian veins. It should be appreciated, however, that therestriction members can be implanted in other manners.

As shown in FIG. 11, the catheter system 800 for treating edema includesan indwelling catheter tube or shaft 802 configured to be placed withina vein of a patient. The indwelling catheter shaft 802 has a lumenextending therethrough that receives a drive shaft 803 therein, whereina distal portion of the drive shaft 803 is operatively coupled to animpeller 815. The catheter system 800 also includes a first selectivelydeployable restriction member adjacent 812 that is proximal to theimpeller 815, and a distal atraumatic tip 808 extending distally from animpeller housing 830 that encompasses the impeller 815. As shown, thefirst restriction member 812, which can be in the form of a distalballoon, has a membrane 816 operatively coupled thereto and configuredto direct fluid from an upstream side of the first restriction member812 to the impeller 815. Similar to membrane 716 (FIG. 9A). The membrane816 can be a conical (distally tapered) membrane defining a tunneltherethrough, though the membrane can have any other suitableconfiguration. The catheter 800 also includes a second selectivelydeployable restriction member 814 (e.g., in the form of a proximalballoon) proximal to the first restriction member 812.

In some embodiments, the catheter system 800 includes one or morepressure sensors. For example, as shown in FIG. 11, the catheter system800 can include a pressure sensor S1 disposed between the distal andproximal restriction members 812, 814. Additionally, the catheter system800 can include one or both of a pressure sensor S2 disposed proximallyto the proximal restriction member 814 and a pressure sensor S3 disposeddistally to the distal restriction member 812. The sensors S1, S2, S3can be coupled to the catheter system 800 in any suitable manner. Itshould be appreciated that the S1, S2, S3 are shown in FIG. 11schematically for illustration purposes only, and one or more of thesensors S1, S2, S3 can be disposed within a lumen, such as control lumenextending through the system, such that the sensor will not be visiblein the manner as shown in FIG. 11. Furthermore, in some implementations,the sensors S1, S2, S3 may not be coupled to the catheter system 800.The sensors can transmit acquired data, via a wireless or wiredconnection, to a suitable controller that processes the data. A motor(e.g., motor 740 in FIG. 22, or any other motor) configured to controloperation of the impeller assembly 805 can be controlled based on thepressure data acquired by the sensors.

The second restriction member 814 is operatively coupled to a flowregulation component 836 configured to direct a controlled volume offluid from an upstream side 807 of the second restriction member 814 toa downstream side 809 of the second restriction member 814. For example,the jugular flow enters through radial openings formed in the flowregulation component 836 (which can be configured similarly to flowregulation component 736 of FIG. 10A) and follows to the gap between thecatheter shaft and an inner lumen of the second restriction member 814.In this way, as shown by arrows in FIG. 11, blood flows from theupstream side 807 of the second restriction member 814, enters a portionof the catheter between the first and second restriction members 812,814, and is directed to the downstream side 809 of the secondrestriction member 814. The components through which the blood flowshave a common lumen extending therethrough. The impeller 815 is rotatedvia a draft shaft by a suitable motor. The impeller 815, as well asother components of the system 800, can be similar to respectivecomponents of the system 700 shown in FIGS. 7, 8, 9A, and 9B, and theirdescription is therefore not repeated herein.

In FIG. 11, the first and second restriction members 812, 814 are shownin the deployed configuration. The first restriction member 812 can be,for example, doughnut shaped and it can allow for a maximum free flow offluid through its lumen and for minimal resistance to the fluid flow. Asshown in FIG. 11, the first and second restriction members 812, 814 canbe implanted so as to create a low pressure zone 811 therebetween. Inuse, the system 800 is operated so as to regulate a fluid flow in thelow pressure zone 811. Transporting the fluid through the localized lowpressure zone 811 can maintain a constant pressure within the lowpressure zone. The second (proximal) restriction member 814 isconfigured to regulate the jugular flow, and it is configured torestrict the blood flow. The conical membrane 816 can allow fordiffusing the fluid flow from the low pressure zone 811 to the impeller815.

In the example of FIG. 11, when the impeller 815 is activated, the bloodflows (arrows 817) from a proximal side of the proximal restrictionmember 814, through the lumen in the restriction member 814, and exits(arrows 819) the restriction member 814 distally into the low pressurezone 811. The blood then flows towards (arrows 821) and through a lumenof the distal restriction member 812, and the bloods exits (arrows 823)the catheter system 800 through openings in an impeller housing 830 thathouses the impeller 815 of an impeller assembly 805. The membrane 816coupled to the distal restriction member 812 directs the blood flow fromthe lumen of the distal restriction member 812 to the impeller 815.

The catheter system 900 shown in FIG. 12 can be configured similar tosystem 800 of FIG. 11. Thus, as shown, the catheter system 900 includesa catheter shaft or 902, distal and proximal selectively deployablerestrictors 912, 914 disposed at least partially around the tube 902, animpeller system 915 including an impeller housing 930 and an impeller905, and a distal atraumatic tip 908 extending distally from theimpeller housing 930. In the example of FIG. 12, when the impeller 915is activated, the blood flows (arrows 917) from a proximal side of theproximal restriction member 914, through a lumen in the restrictionmember 914, and exits (arrows 919) the restriction member 914 distallyinto the low pressure zone 911. The blood then flows towards (arrows921) and through a lumen of the distal restriction member 912, and thebloods exits (arrows 923) the catheter system 900 through openings in acage or impeller housing 930 that houses the impeller 915 of an impellerassembly 905. The membrane 916 coupled to the distal restriction member912 directs the blood flow from the lumen of the distal restrictionmember 912 to the impeller 915. Although not shown in FIG. 12, similarto system 800 of FIG. 11, the system 900 (as well as other cathetersystems described herein) can include one or more pressure sensors, suchas, for example, one or more of the sensors S1, S2, S3 (FIG. 11).

It should be appreciated that the described embodiments include animplantable catheter system that can have any of the components of thecatheter systems 700, 800, and 900 (which, in turn, can be similar toone another). Also, any of the components of one of the catheter systems700, 800, and 900 can be included into another one of the cathetersystems 700, 800, and 900.

Any of the catheter systems described herein can be associated with anyother components. For example, a catheter system can include acontroller that can be configured to be in electronic communication withat least one pressure sensor (not shown). A person skilled in the artwill appreciate that a variety of suitable sensors can be used formonitoring pressure, such as central venous pressure (CVP) or otherfluid pressure sensors, and blood pressure sensors. The pressuresensor(s) can be implanted in the patient as part of the impeller,implanted in the patient as a separate component from the impeller, orthe at least one pressure sensor can be located external to the patient,such as by being on a skin surface thereof. If not already a part of theimpeller so as to be in electronic communication therewith, the at leastone pressure sensor can be configured to be in electronic communicationwith the impeller over a communication line such as a wired line or awireless line.

In an exemplary embodiment, three pressure sensors can be implanted inthe patient. One of the pressure sensors can be implanted between thefirst and second restriction members as to be in the low pressure zone.Another pressure sensor can be implanted in the vein proximal to thesecond restriction member, and another pressure sensor can be implantedin the vein distal to the first restriction member, so as to be in thehigher pressure zones. The sensors can allow a pressure differential tobe determined between the low pressure zone and the higher pressurezone. In other embodiments, another number of pressure sensors can beimplanted in the patient (e.g., one, three, four etc.) and/or thepressure sensor(s) can be implanted at other locations.

The catheter can include at least one lumen (not shown) configured tofacilitate use of the pressure sensor(s), for example to facilitateplacement of the pressure sensor(s) and/or to be filled with a fluidsuch as saline to allow for external pressure measurement.

In addition to or instead of the one or more pressure sensors, thecontroller can be configured to be in electronic communication with atleast one other type of sensor (not shown) configured to sense aparameter other than pressure. Examples of sensors that can be used tomeasure a parameter other than pressure include radio frequencytransmitters and receivers, fluid sensors, bioimpedance sensors, heartrate sensors, breathing sensors, activity sensors, and optical sensors.Examples of the measured parameter include fluid amount (e.g., asmeasured by a fluid sensor, such as a fluid sensor placed in a lung tosense fluid amount in the lung), bioimpedance (e.g., as measured by abioimpedance sensor), heart rate (e.g., as measured by a heart ratesensor), breathing rate (e.g., as measured by a breathing sensor),patient activity level (e.g., as measured by an activity sensor), andorgan dimension (e.g., as measured by an optical sensor). The sensor canbe implanted in the patient as part of the pump, implanted in thepatient as a separate component from the pump (e.g., implanted in aninterstitial space around a lung, implanted at a junction of a rightsubclavian vein of a patient and an internal jugular vein of thepatient, implanted at a junction of a left subclavian vein of a patientand an internal jugular vein of the patient, etc.), or the sensor can belocated external to the patient, such as by being on a skin surfacethereof.

The controller can include any type of microprocessor or centralprocessing unit (CPU), including programmable general-purpose orspecial-purpose microprocessors and/or any one of a variety ofproprietary or commercially available single or multi-processor systems.The controller can be a component of a control system that includes anynumber of additional components, such as a memory configured to canprovide temporary storage and/or non-volatile storage; a bus system; anetwork interface configured to enable the control system to communicatewith other devices, e.g., other control systems, over a network; and aninput/output (I/O) interface configured to connect the control systemwith other electronic equipment such as I/O devices (e.g., a keyboard, amouse, a touchscreen, a monitor, etc.) configured to receive an inputfrom a user. The controller can be configured to receive user inputthereto to control any of a variety of aspects related to the catheter,such as speed of the motor and ideal range of pressure for the lowpressure zone.

In use, the catheter system can be attached to a patient near anincision point. One or more electronic cables can be connected to amultiuse console that includes a motor controller, a pressure sensoramplifier, firmware with data acquisition system, power supply, touchscreen monitor, and any other suitable components.

In some embodiments, a method of implanting a catheter system involvesdelivering a sterile catheter kit to a clinical site in its open state,in which a distal portion of a distal assembly is unsheathed. Prior toan implanting procedure, a user (e.g., a physician assistant or anyother medical professional) can insert the distal assembly into a sheathlumen, e.g., by using a handle Tuhy. The catheter is then inserted bythe physician over a guide wire into the jugular vein (e.g., posteriorapproach). Once it is confirmed (using, e.g., an ultrasound technique)that the catheter is located in the jugular vein, the operator canun-sheath the distal unit in two consecutive steps. First, the distalballoon can be un-sheathed and positioned in the innominate vein justpast the subclavian drainage. Second, the proximal balloon is disposedin the jugular vein, above the subclavian vein.

The guide wire can be pulled out and the sheath is fixated to the skinin a location that allows the maximal axial adjustment of the assembly.After the fixation, the centralizer is positioned, and an electric cableis connected. The motor is activated (e.g., using a controller that canbe accessed via a console graphical user interface (GUI)) and causes thedistal and proximal balloons to inflate. The distal balloon can beinflated prior to inflating the proximal balloon. The CVP can bemeasured through a sheath luer. The pressure can be adjusted using acatheter system handle by bringing a proximal assembly of the catheterassembly closer to the sheath or away from the sheath (or any othermechanism). The motor can drive the impeller to define a low pressurezone by causing fluid to be pumped through the catheter system. In thisway, the system can operate automatically to keep the low pressure zone(or “isolated zone”) at a nominal pressure value of, for example,2.5±2.5 mmHg. This can be done be controlling the motor RPM.

In general, the described catheter system is configured to seal a zoneat the bifurcation of the patient's jugular and subclavian veins usingthe distal and proximal balloons. As the impeller is operated, the bloodis directed from the low pressure zone such that the pressure insidethat zone is reduced. The motor receives feedback from one or morepressure sensors, and the pressure can be regulated by the motor RPM.The CVP can be adjusted by a regulation mechanism at the proximalassembly.

The described systems (e.g., any of the systems 700, 800, 900) providevarious advantages over existing systems. For example, because arestrictor in the form of a balloon is inflated over the entire vesselperimeter and the suction lumen is an integrated part of the balloon,the vessel is prevented from collapsing on the suction lumen and thusblocking the blood entrance. Furthermore, since there is a free passagebetween the isolated zone and the innominate vein, in case of amalfunction or unintentionally stopping of the system, a pressureelevation event will be prevented in the isolated zone and stagnation ofblood can be prevented.

The conical shape of the membrane, the large suction diameter and theminimal length of flow up to the impeller can provide a minimalresistance to blood flow during suction and therefore increases theimpeller ability to pump the required amount of blood at a lowerrotational speed as compared to other systems. Mechanical hemolysis canoccur due to high shear stresses on the blood cells. Thus, the lower therotational speed of the impeller, the lower the shear stress, whichincreases safety of the catheter system. Additionally, a lowerrotational speed provides a wider range of flow rate and reduces apossibility of the system not being able to reduce the pressure becauseof a rotational speed limitation.

As another advantage, the described catheter system can eliminate a needfor a conduit coupled between the jugular vein and the innominate andallows for pressure regulation in the jugular vein. Thus, unavoidablepressure elevation of the jugular vein does not take place. Furthermore,the proximal and distal balloons are configured to be inflated usingseparate mechanisms of the proximal and distal assemblies, respectively,a distance between the proximal and distal balloons can be determinedand adjusted. This provides an additional flexibility of the systemwhich allows adjusting the system to the specific anatomy of a patient.

In some embodiments, a catheter system is associated with aninfusion/purging system configured to infuse fluids into a certainportion of the catheter system to thereby prevent an undesirable eventof the blood entering that portion. Thus, FIG. 23A illustratesschematically a system 1001 in which some embodiments can beimplemented. The system 1001 includes a catheter system 1000 that can beat least partially implanted into a patient 1111, a control system 1004coupled to the catheter system 1000, and an infusion system 1006. Thepatient 1111 has an incision through which the catheter system 1000 isdelivered into the patient. As shown in FIG. 23A, the catheter system1000, which is also shown enlarged in an inset 1007 in FIG. 23B, can becoupled to a fixture or holder device 1017 that is worn by the patient1001. The holder device 1017 can have any suitable configuration thatallows it to assist in maintaining a position of the catheter system1000 with respect to a patient's body. In this example, the holderdevice 1017 is in the form of a collar-like device configured to becoupled to the patient's neck. The control system 1004, which is, inthis example, in the form of a console device, has various components,non-limiting examples of which include a motor controller, a pressuresensor amplifier, a processing hardware including a data acquisition andprocessing system, and a power supply. The control system 1004 includesprocessors configured to acquire, process, and analyze data collectedduring operation of the catheter system 1000.

As shown in FIG. 23A, the control system 1004 includes a display 1009that can be a touch screen display. The display 1009 is configured todisplay information related to operation and control of the cathetersystem 1000. The control system 1004 can be coupled to the cathetersystem 1000 via a cable 1019; however, in some embodiments, theconnection can be wireless such that the control system 1004 or a partthereof can be located remotely to the catheter system 1000. Theinfusion system 1006, having an infusion container 1106 (e.g., a bag orany other type of a container), is configured to allow fluid to access aspace between a drive shaft 1003 (shown in FIG. 25) and a sleeve of thecatheter system 1000 that encloses at least a portion of the drive shaft1003, as discussed in more detail below.

FIG. 24 illustrates the catheter system 1000 in more detail. As shown inFIG. 24, the catheter system 1000 includes a catheter tube 1002, distaland proximal restrictors or restriction members 1012, 1014, a distal tip1008, and an impeller system 1005. A proximal portion 1022 of thecatheter system 1000 includes, among other components, a motor 1040 andfans 1041. The motor 1040 can be similar to motor 740 (FIG. 7). Theproximal portion 1022 can be in the form of a handle at least a portionof which can be held by a user when the catheter system 1000 is insertedinto the patient's body. Similar to distal restrictor 712 (FIGS. 7, 8,and 9A), the distal restriction member 1012 has a membrane 1016 coupledthereto. In this embodiment, the distal and proximal restriction members1012, 1014 are in the form of expandable elements, such as balloons,each of which is configured to at least partially restrict a vessel(e.g., a vein) of a patient in which it is implanted. Thus, the distaland proximal restriction members 1012, 1014 are moveable between apre-activated (e.g., not expanded or non-inflated) and activated (e.g.,expanded or inflated) configurations. In the illustrated embodiments, adiameter of the inner lumen of the distal restriction member 1012 can begreater than a diameter of an inner lumen of the proximal restrictionmember 1014. In this way, whereas the proximal restriction member 1014reduces a blood flow that passes therethrough (e.g., causes the jugularflow to reduce), the distal restriction member 1012 allows a largervolume of the blood flow to pass therethrough. Furthermore, in someimplementations, the distal restriction member 1012 allows blood to flowfreely through its lumen.

FIG. 25 shows a distal portion of the catheter system 1000 in moredetail. Thus, as shown, the impeller system 1005 includes an impeller1015 disposed within an impeller housing 1030 that also includes abearing system 1013 shown separately in FIG. 26A. The membrane 1016coupled to the distal restriction member 1012 has a conically-shapedportions, as membranes in other embodiments described herein. It shouldbe appreciated, however, that the membrane 1016 can additionally oralternatively have other configurations.

FIG. 26B illustrates one embodiment of a catheter shaft or tube 1002′ ofa catheter system in accordance with the described techniques, such as,for example, the catheter tube 1002 of FIG. 24. As shown, the cathetertube 1002′, shown in FIG. 26B in cross-section, includes an inner lumen1046′ configured to receive a sleeve and a drive shaft, with the driveshaft received within a sleeve's lumen. In this example, the cathetertube 1002′ also includes lumens 1048. In this embodiment, the lumens1048 include a proximal restrictor inflation lumen, a distal restrictorinflation lumen, a pressure sensor lumen, and an infusion (or “purge”)lumen. These four lumens can be disposed in any suitable order withinthe catheter tube 1002′. Furthermore, it should be appreciated that thecatheter tube 1002′ can have other lumens, and it can have fewer orgreater than four lumens.

FIG. 26C illustrates the proximal restriction member 1014 having aninner lumen 1019 configured to receive the drive shaft 1003therethrough. The lumen 1019 is configured to pass fluid (e.g., blood)therethrough. In some embodiments, a diameter of the fluid flow lumen1019 of the proximal restriction member 1014 in an activated (e.g.,inflated) configuration is less than a diameter of a fluid flow lumen ofthe proximal restriction member 1012 in an activated (e.g., inflated)configuration.

As in the other embodiments described herein, the catheter system 1000is configured to reduce pressure in a specified partially isolated zone,which becomes a low pressure zone. The isolated zone is defined betweenthe distal and proximal restriction members 1012, 1014 when therestriction members 1012, 1014 are implanted in the patient's body andare activated (e.g., inflated). A blood pressure between the implanteddistal and proximal restriction members 1012, 1014 is reduced when theblood is pumped out at a higher rate than can be supplied by thesurrounding veins. The pumping of the blood can be accomplished by usinga motor that is configured, when activated, to rotate a drive shaft 1003inside a sleeve component. A distal end 1003 d of the drive shaft 1003is coupled to the impeller 1015 that is supported by the bearing system1013 disposed within the impeller holder or housing 1030. The impeller1015, which can be similar to impeller 715 (FIG. 15), is configured topump blood in an axial direction through the membrane 1016 and todischarge the blood radially through radial openings in the impellerhousing 1030. The impeller housing 1030 is configured similar toimpeller housing 730 (FIG. 16) that has radial openings 732, and theimpeller housing 1030 therefore has similar radial openings configuredto discharge blood therethrough. In some embodiments, however, theimpeller housing 1030 can be configured similar to impeller housing 730′(FIG. 17), or the impeller housing 1030 can have other configurationsuch that blood is discharged from inside the housing to the outer sidethereof.

The catheter system 1000 includes at least one pressure sensor disposed,e.g., between the distal and proximal restriction members 1012, 1014,and such pressure sensor(s) acquire data indicative of measurements ofblood flow in a zone between the restriction members 1012, 1014. Themotor that activates the impeller 1015 can be controlled such that anincrease in an RPM (revolutions per minute) of the motor results in adecrease of the pressure in the zone between the distal and proximalrestriction members 1012, 1014.

FIG. 27 illustrates a portion of the catheter system 1000 having thecatheter tube 1002 (a multi-lumen tube) that has a tubular sleeve 1070extending through its inner lumen. The sleeve 1070 has the drive shaft1003 extending therethrough, and the drive shaft 1003 rotates inside thesleeve 1070. A space or gap 1072 between an outer wall of the driveshaft 1003 and an inner wall of the sleeve 1070 is not hermeticallysealed. Accordingly, in some embodiments, an infusion/purging system isprovided that allows to fill the gap 1072 between the drive shaft 1003and the sleeve 1072. The gap 1072 can be filled with fluid to avoidpenetration of air into the patient's venous system and blood leakageinto the catheter tube. Referring back to FIG. 23, the system 1001includes the infusion system 1006 configured to deliver a fluid into thegap 1072 between the drive shaft 1003 and the sleeve 1072. Becausefluid(s) are delivered through the relatively narrow gap 1072, at acontrolled rate, the infusion/purging system 1006 can allow infusingfluid(s) to a patient which has fluid intake limitations. The infusionsystem 1006 is also configured to flash to the blood stream particlesand other material that can be produced, for example, due to frictionbetween the drive shaft and the sleeve.

In use, the infusion system 1006 is configured to deliver a fluid to thegap 1072 between the drive shaft 1003 and the sleeve 1070 via aninfusion port 1009. In the illustrated embodiment, the fluid can flowfrom the infusion port 1009 proximally towards a proximal end or point1112 of the gap 1072 and/or from the infusion port 1009 distally towardsa distal end or point 1110 of the gap 1072. The fluid can be, forexample, saline heparin or saline, or other suitable fluid. The fluidcan be delivered at a relatively slow rate such as, for example, in arange from about 1 ml/hr to about 10 ml/hr. Referring back to FIG. 23,in some embodiments, an infusion line 1108 between the infusioncontainer 1106 and the catheter system 1000 can be coupled to a proximalport on the catheter's multi-lumen tube 1002. The infusion container1106 releasably storing the fluid can be located at a height in a rangefrom about 10 cm to about 40 cm relative to a point of incision createdin the patient to deliver the catheter system 1000. The rate of thefluid delivery can be controlled by adjusting a height of the infusioncontainer 1106 relative to the catheter system 1000. As shown in FIG.27, the infusion system, which delivers the infusion fluid to thecatheter system 1000 via the infusion port 1009, can flash particles outfrom the catheter tube through the proximal purge outflow towards theproximal point 1112. A minimum amount of fluid can be delivered into thepatient from the infusion port 1009 and through the distal purge outflowtowards the distal point 1110, thereby preventing blood from flowing upand into the catheter (i.e., to the left in FIG. 27). In addition, insome embodiments, the fluid can be delivered into the gap 1072 through agap's distal point or side 1110. The distal point 1110 can be disposed,e.g., at about 1-2 cm proximal to the impeller 1015. In the illustratedembodiments, a first volume of the infusion/purge fluid can flowproximally (from the infusion port 1009 towards the proximal point1112), and a second volume of the infusion/purge fluid can flow distally(from the infusion port 1009 towards the distal point 1112), with thefirst volume being greater than the second volume.

In the illustrated embodiment, a distance between the infusion port 1009and the distal end 1110 of the gap 1072, as well as a distance betweenthe infusion port 1009 and the proximal end 1112 of the gap 1072determine a resistance to blood flow in the patient's body that can becreated by the infusion fluid flowing through the catheter system. Inparticular, the ratio of these distances determines the resistance ofthe infusion flow to the blood flow. Thus, the closer the infusion port1009 is to the distal end 1110 of the gap 1072, the higher is the distalpressure of the infusion fluid that blocks blood from entering the gap1072. In this way, the ratio of the distances between the infusion port1009 and the distal end 1110 of the gap 1072 and between the infusionport 1009 and the proximal end 1110 of the gap 1072, as well as theheight of the infusion container 1106 relative to the catheter system1000 at least partially implanted into the patient, together controlresistance to the flow and the pressure of the fluid introduced into thesystem 1000 through the infusion port 1009. In some embodiments, theheight of the infusion container 1106 can be adjusted so as to deliverthe fluid through an infusion port 1009, such that the fluid leaves thegap 1072 via a proximal side 1112 of the gap 1072. The flow rate can beadjusted by the height of the infusion container creating a pressuregradient that determines the flow rate. The height of the infusioncontainer minus the blood pressure at the distal purge defines thedriving force for the flow of fluids into the patient. In order toprevent blood from flowing up into the catheter, there has to be flowinto the patient. It is desirable to have this flow into the patient assmall as possible so as not to overload the patient with fluids.Accordingly, the height of the infusion container 1106 is adjusted so asto achieve a pressure gradient of about 5 mmHg, such that theinfusion/purge fluid flows into the patient in a rate that is equal toor less than 2 ml/hr. The delivery of the fluid through the infusionport 1009 allows the fluid to flow from the infusion port 1009, throughthe gap 1072, and towards the distal side 1110. When the air orliquid(s) flow through the gap 1072 towards the proximal side 1112, asin the described embodiment, this may additionally assist in cooling themotor 1040.

FIGS. 28 and 29 show examples of implantable catheter systems in whichthe described embodiments can be implemented. Thus, FIG. 28 shows acatheter system 1200 having a catheter tube 1202, an impeller 1215, anddistal and proximal restriction members 1212, 1214, which are shown inFIG. 28 in the activated (e.g., inflated) configuration. The cathetersystem 1200 can be similar to any of the system 1000 (FIGS. 23 and 24),system 700 (FIG. 7), system 800 (FIG. 11), and system 900 (FIG. 12) andis therefore not described in detail herein. As shown in FIG. 28, thecatheter system 1200 can be implanted into the patient's body such thatthe distal restriction member 1212 is disposed in the innominate vein1222 in proximity to the subclavian vein 1226, and the proximalrestriction member 1214 is disposed proximal to the distal restrictionmember 1212 in the jugular vein of the patient at least about 1 cmbefore its confluence with the subclavian vein so as not to block theoutflow of the thoracic duct. The same apparatus can be in either leftor right sides of the neck, i.e., inserted through the right or leftinternal jugular veins. In some embodiments, an inner lumen of theproximal restriction member 1214 can have a diameter that is less than adiameter of an inner lumen of the distal restriction member 1212.However, in some implementations, these diameters can be substantially(e.g., with a small deviation, such as, e.g., from about 5% to 10%) thesame.

In this example, as shown in FIG. 28, the proximal restriction member1214 is moved into the activated (e.g., inflated) configuration suchthat its outer surface is spaced away from the inner wall of the jugularvein 1226. In this way, a diameter of the expanded proximal restrictionmember 1214 is less than a diameter of the expanded distal restrictionmember 1212, and the fluid is allowed to be passed in the gap betweenthe outer surface of the proximal restriction member 1214 and an innerwall of the vein. The catheter system 1200 can be attached at animplantation site at the vein such that its position is maintained, andsuch that the proximal restriction member 1214 is disposed approximatelycentrally within the vein.

FIG. 29 illustrates a catheter system 1300 having a catheter tube 1302,an impeller 1315, and distal and proximal restriction members 1312,1314, which are shown in FIG. 29 in the activated (e.g., inflated)configuration. The catheter system 1300 can be similar to any of thesystem 1000 (FIGS. 23 and 24), system 700 (FIG. 7), system 800 (FIG.11), system 900 (FIG. 12), and system 1200 (FIG. 28), and is thereforenot described in detail herein. As shown in FIG. 29, the catheter system1300 can be implanted into the patient's body such that the distalrestriction member 1312 is disposed in the innominate vein 1322 inproximity to the subclavian vein 1324, and the proximal restrictionmember 1314 is disposed proximal to the distal restriction member 1312in the jugular vein 1326 of the patient. In this example, as shown inFIG. 29, the proximal restriction member 1314 is moved into theactivated (e.g., inflated) configuration such that its outer surface isadjacent to the inner wall of the jugular vein 1326. In this way, therestriction member 1314 can be inflated such that its outer surface isin contact with the inner wall of the jugular vein 1326. In someembodiments, an inner lumen of the proximal restriction member 1314 canhave a diameter that is less than a diameter of an inner lumen of thedistal restriction member 1312. However, in some implementations, thesediameters can be substantially (e.g., with a small deviation, such as,e.g., from about 5% to 10%) the same.

As shown in FIGS. 28 and 29, the catheter system can be implanted suchthat a zone at the bifurcation of the patient's jugular and subclavianveins in proximity to an outflow of a thoracic duct (1223 in FIGS. 28and 1323 in FIG. 29) is at least partially sealed using the distal andproximal restriction members. Once the impeller of the catheter systemis operated by a motor, the blood is caused to be pumped and thepressure inside an isolated zone will be dropped. Thus, FIG. 28 shows alow pressure zone 1211 that is created between the distal and proximalrestriction members 1212, 1214. Similarly, FIG. 29 shows a low pressurezone 1311 that is created between the distal and proximal restrictionmembers 1312, 1314.

In the example of FIG. 28, when the impeller 1215 is activated, bloodflows (arrows 1217) from a proximal side of the proximal restrictionmember 1214 such that the blood passes between the outer surface of theproximal restriction member 1214 and an inner wall of the vein. Theblood can also flow through an inner lumen of the proximal restrictionmember 1214. The blood then follows from the proximal restriction member1214 towards (arrows 1219) and through a lumen of the distal restrictionmember 1212, and the bloods exits (arrows 1221) the catheter system 1200via openings in an impeller housing 1230 having the impeller 1215therein. Similar to other embodiments, the blood is directed from thelumen of the distal restriction member 1212 to the impeller housing 1230via a membrane 1216, such as, e.g., a conical membrane.

In the example of FIG. 29, when the impeller 1315 is activated, theblood flows toward (arrows 1317) and through (arrows 1319) a lumen ofthe proximal restriction member 1314, towards (arrows 1321) and througha lumen of the distal restriction member 1312, and the bloods exits(arrows 1323) the catheter system 1300 via openings in an impellerhousing 1330 having the impeller 1315 therein. The blood is directedfrom the lumen of the distal restriction member 1312 to the impellerhousing 1330 via a membrane 1316, such as, e.g., a conical membrane. Asdiscussed above, one or more pressure sensors can be disposed betweenthe distal and proximal restrictors, and/or on one or both sides of therestrictors. The blood pressure is regulated by controlling a motor RPMbased on blood pressure measurements acquired from the sensors.

It should be appreciated that, although not shown, the catheter system1000 (FIGS. 24, 25, and 27), catheter system 1200 (FIG. 28), andcatheter system 1300 (FIG. 29) can include or can be associated with oneor more pressure sensors, such as, for example, one or more of pressuresensors S1, S2, S3 (FIG. 11). Furthermore, any of the catheter systemsdescribed herein can be associated with sensors of any other type.

A catheter system, such as, for example, catheter system 1200, cathetersystem 1300, or any other catheter system in accordance with thedescribed subject matter, can be delivered into an implantation site invarious ways. In some embodiments, an introducer sheath is insertedthrough an incision and into the jugular vein of a patient, e.g.,approximately 10 cm above the subclavian vein junction (venous angle).The catheter system, having distal and proximal restrictors in anon-deployed configuration, is then inserted over a guide wire into thejugular vein (posterior approach). The catheter system is inserted suchthat the proximal restrictor, in a non-deployed configuration, ispositioned in the jugular vein, e.g., about 1.5 cm above (toward thepatient's head) the subclavian drainage. Once it is determined (e.g.,using ultrasound or another imaging technique) that the catheter systemis positioned as desired, the guide wire is removed. The sheath is thenattached to the patient (e.g., to the patient's skin) at a location thatallows for axial adjustment of the catheter system. The catheter systemcan be associated with one or more pressure sensors.

Once the sheath is attached to the patient, fluid, such as, e.g.,heparin bolus, is administered to the patient and a motor coupled to thecatheter system can be connected to a power source and to an infusionsystem. The motor can be activated to operate, e.g., at 22 k RPM (oranother rate) to allow a constant blood flow through the blood pathway.The distal restrictor is then deployed (inflated) to radially expand soas to constrict the vein. The proximal restrictor is then deployed untila change in pressure is detected (e.g., using the pressure sensor(s)).The inflation of the distal restrictor is then determined to becompleted, and the motor is controlled based on a predefined pressurevalue. Such value can be set via a suitable control system. The CVP isbe measured trough the sheath luer at any time point from this pointforward the system will be operated automatically to keep isolated zoneat nominal pressure value of about 2.5 mmHg by controlling the motorRPM.

The embodiments described in connection with FIGS. 23-29, which includea catheter system associated with an infusion system, can providevarious advantageous features. For example, because at least one of thedistal and proximal restrictors is deployed (e.g., inflated) to occupyat least partially the perimeter of a vessel in a patient's body, andbecause a suction lumen is defined by the restrictors, the vessel isprevented from collapsing on the suction lumen and thus blocking theblood entrance. Furthermore, because there is a free passage between theisolated zone and the innominate vein, in case of a malfunction of thesystem or an unintentional interruption of a motor, a risk ofundesirable pressure elevation and blood stagnation within the isolatedzone is decreased or eliminated. Furthermore, the configuration of thesystem's components, such as a membrane with a conically-shaped portion,a relatively large suction diameter of the distal restrictor and aposition of the impeller in proximity to the distal restrictor allowsachieving a decreased resistance to blood flow during suction. Thisallows the impeller to pump the required amount of blood at a reducedrotational speed, which decreases a possibility of mechanical hemolysis(which can occur due to high shear stresses on the blood cells) andimproves overall safety of the catheter system. Additionally, a need fora jugular flow bypass can be eliminated. Furthermore, flow rates andblood pressure are controlled by controlling the motor to increase anddecrease RPM continuously and in real time. In this way, the operationof the system can account for the pressure changes in the venous systemdue to the heart beats and breathing.

It should be appreciated that the catheter system described inconnection with FIGS. 23-29 can have any suitable variations. Also,other components can be used in conjunction with the catheter system tofacilitate blood pressure reduction in the patient's vein in a desiredmanner. For example, in at least one embodiments, a venous constrictorcuff of any suitable configuration can be placed on the patient'sforearm so as to restrict subclavian vein flow to a rate in a range fromabout 50 ml/min to about 100 ml/min, thus enabling less blood needing tobe circulated by the impeller.

In some embodiments, various systems and methods are provided fortreating edema, for example, chronic fluid overload or other edema. Ingeneral, a pump can be configured to be implanted within a patient atrisk of developing edema. The pump can be configured to pump fluid outof the patient's lungs, e.g., out of the patient's interstitial andalveolar spaces. The pump can be configured to be fully implanted withinthe patient's body. The pump can be configured to continuously pumpfluid, or the pump can be configured to be selectively actuatable inresponse to a trigger event. In an exemplary embodiment, the pump caninclude an inflow port coupled to an inflow tube in fluid communicationwith a lymphatic vessel of the patient, an outflow port coupled to anoutflow tube in fluid communication with a vein of the patient, and animplantable battery.

Accordingly, in some embodiments, various systems and methods areprovided for reducing pressure at an outflow of a duct such as thethoracic duct or the lymphatic duct, such as the right lymphatic duct.In general, the systems and methods may be effective to reduce edemaconditions, such as, for example, fluid overload, in a patient bylowering an outflow pressure in a region around the patient'sthoracic/lymphatic duct outflow. As a result of lowering the outflowpressure at the thoracic and/or lymphatic ducts, higher lymphatic returnwill be achieved, enabling the lymphatic vessel flow to be at or nearnormal levels. The systems and methods may be effective to alleviateconditions of the edema and increase the patient response rate. Inexemplary embodiments, the systems and methods may be particularlyuseful to treat long-term, or chronic, fluid overload, however a personskilled in the art will appreciate that the systems and methods can beused in various procedures for treating a lymphatic system fluidclearance imbalance.

At least some embodiments described herein generally relate to systemsand methods for treating chronic fluid overload. In general, a pump canbe configured to be implanted within a patient at risk of developingedema. The pump can be configured to pump fluid out of the patient'slungs, e.g., out of the patient's interstitial and alveolar spaces,which can help prevent the fluid from building up to a dangerous degree.The pump can thus be configured to facilitate prevention of edema bylimiting fluid build-up in the lungs, if not preventing fluid build-upentirely. In other words, the pump can be configured to facilitatetreatment of chronic edema, such as can occur in connection with chronicheart failure. The pump can be configured to facilitate higher lymphaticreturn by lowering outflow pressure at a lymphatic vessel of thepatient, e.g., at the patient's thoracic duct and/or lymphatic duct, forexample, the right lymphatic duct.

The pump can be configured to be fully implanted within the patient'sbody, thereby helping the device to be unobtrusive in the patient'sdaily life, similar to a pacemaker. The pump can be configured to beoperated using a battery. In some embodiments, a single battery can beused for any suitable time period during which the pump remainsimplanted in a patient's body. The pump can be configured tocontinuously pump fluid, which can help ensure the removal of fluid thatcollects in the lung space before a dangerous amount of the fluid buildsup and/or can help ensure the long term patency of the pump.Alternatively, the pump can be configured to be selectively actuated inresponse to a trigger event, such as in response to a value of ameasured parameter (e.g., pressure, fluid amount, bioimpedance, heartrate, breathing rate, patient activity level, organ dimension, etc.) orin response to receiving a user input requesting pumping. The pump canthus be configured to only periodically pump fluid, e.g., onlyperiodically run so as to alternate between periods in which the pump isrunning to provide fluid flow and in which the pump is not running.Running periodically can help conserve power (e.g., battery power)and/or can be appropriate for patients with lower risks of developingedema and/or for patients who tend to be more at risk of developingedema at certain times (e.g., during the day instead of at night, whenexercising, etc.) instead of having a more constant risk. In at leastsome embodiments, the pump can be configured to be selectively switchedbetween a continuous mode in which the pump runs continuously and aperiodic mode in which the pump runs periodically, which can help thepump be most effectively used according to each patient's current needs.

In some embodiments, the system can include any one or more of thefollowing components: an implantable device that includes an implantabledevice, an implantable pump, one or more sensors, and a controller. Thecomponents of the system can operate to alleviate chromic fluidoverload.

FIG. 30 illustrates an example of an implantable device 2100 inaccordance with some implementations of the current subject matter. Theimplantable device 2100 is configured to be implanted in a body of apatient and can be used to withdraw lymph fluid from the thoracic ductof a patient, as shown schematically in FIG. 30. The implantable device2100 includes an inlet or inflow tube 2104, an outlet or outflow tube2106, and an implantable pump 2108. The inflow and outflow tubes 2104,2106 are connected to the implantable pump 2108 as shown in FIG. 30.

As illustrated, the inflow tube 2104 having an inflow opening 2110 canbe coupled to an inflow port 2112 of the pump 2108, and the outflow tube2106 having an outflow opening 2114 can be coupled to an outflow port2116 of the pump 2108. For reference, FIG. 30 also shows the patient'sleft subclavian vein, thoracic duct, left innominate vein and jugularvein. As shown, the inflow opening 2110 of the inflow tube 2104 can bepositioned within the thoracic duct. The valves of the thoracic duct(“valve”) are shown in FIG. 30. The outflow opening 2114 of the outlettube 2106 is positioned within a blood vessel such as, in this example,the jugular vein.

Thus, the pump 2108 in this illustrated embodiment generally provides abypass from the thoracic duct to the left jugular vein, thereby allowingfor a constant draining option for the lymphatic duct (e.g., the rightlymphatic duct) in case venous pressures elevate. The pump 2108 can beconfigured to be automatically activated to drain fluid on demand inresponse to a measured increase in pressure. Also, the pump 2108 can beactivated in response to a user input, or in other manner. A bypass canbe similarly provided by positioning the outflow opening 2114 at thesubclavian vein instead of the left jugular vein.

As shown in FIG. 30, the inflow port 2112 coupled to the inflow tube2104 is in fluid communication with the thoracic duct of the patient,and the outflow port 2116 coupled to the outflow tube 2106 is in fluidcommunication with a vein of the patient, e.g., the patient's internaljugular vein. The outflow port 2116 can alternatively be in fluidcommunication with a subclavian vein, innominate vein (also referred toas a “brachiocephalic vein”), or superior vena cava. The pump can thusbe configured to pump fluid from the thoracic duct to the vein so as tofacilitate removal of fluid from the thoracic duct and therebyfacilitate higher lymphatic return by lowering outflow pressure at thelymphatic vessel. Because lymphatic systems can have different anatomiesin different patients, the inflow tube can be positioned to be in fluidcommunication with the patient's thoracic duct or any duct that drainsinto the patient's subclavian vein, jugular vein, innominate vein, orsuperior vena cava

The implantable pump 2108 can have a variety of sizes, shapes, andconfigurations. In an exemplary embodiment, the pump 2108 can be any oneof a pulsatile pump, a periodical pump, and a continuous flow pump.

The pump 2108 can have a size configured to facilitate implantation ofthe pump 2108 within the patient's lung. In at least some embodiments,the pump 2108 can have a size configured to allow the pump 2108 to beimplanted within a duct of the patient, such as a thoracic duct of thepatient. In an exemplary embodiment, the pump 2108 can have a length ina range of about 2 to 3 cm and a diameter of about 20 mm.

In an exemplary embodiment, the pump 2108 can be configured to pumpfluid at a rate in a range of about 10 to 1000 ml/hour (milliliters perhour), e.g., in a range or about 200 to 600 ml/hour, about 300 ml/hour,about 500 ml/hour, etc. In at least some embodiments, the pump 2108 canhave a static, e.g., unchangeable, flow rate. The flow rate can thus bepredictable and/or chosen for a specific patient. In other embodiments,the pump 2108 can have an adjustable flow rate. The flow rate beingadjustable can help the pump 2108 accommodate changes in the patient'scondition over time. The flow rate can be adjustable in a variety ofways, as will be appreciated by a person skilled in the art, such as bybeing wirelessly adjusted using a user-operated control device locatedexternal to the patient and configured to wirelessly communicate withthe pump 2108 to adjust the flow rate thereof. The pressure gradientthat the pump 2108 discharges against is less than about 15 mmHg. Atotal power of the pump can be in the range from about 0.02 Watt toabout 0.7 Watt. In one embodiment, total power of the pump is about0.166 Watt.

As shown in FIG. 30, the pump 2108 can be powered using an implantablebattery 2120. The battery 2120, which can be rechargeable (includingwirelessly) and/or replaceable, can have electrical capacity from about25 mAh (milliamp Hour) to about 10 Ah. Thus, the battery 2120 can beable to operate for an extended period of time. For example, the totalworking time for the battery 2120 can be 22-9000 hours. In someembodiments, an average number of days that the pump 2108 remainsimplanted in the patient's body can be about 500 days. Thus, in theillustrated implementation, the implantable device 2100, once implanted,can be operated over a relatively long period of time to alleviatechronic edema, using a single battery.

The inflow tube 2104 can be secured to the thoracic duct using anattachment feature 2124 that can be in the form of an implantableballoon, a stent-like self-expanding structure, or an attachment featurehaving any other suitable configuration. The inflow and outflow tubes2104, 2106 tubes can be manufactured from biocompatible materials, suchas, e.g., silicone or thermoplastic polyurethane (TPU). Otherbiocompatible materials can be used additionally or alternatively.

The inflow and outflow tubes 2104, 2106 can each be removably coupled totheir respective ports 2112, 2116 of the pump 2108 or can each bepermanently coupled to their respective ports. The inflow and outflowtubes can each be flexible to facilitate their positioning withintortuous and/or curved lumens in the patient's body. The inflow andflexible tubes can each include, e.g., indwelling catheters. In anexemplary embodiment, both of the inflow and outflow tubes are coupledto the pump 2108 in a same manner, e.g., both removable or bothpermanent. As will be appreciated by a person skilled in the art, fluidcan be configured to flow in to the pump 2108 through the inflow portand out of the pump 2108 through the outflow port, thereby facilitatingpumping of the fluid.

The pump 2108 can be powered in a variety of ways. In at least someembodiments, the pump 2108 can be configured to be powered by animplantable power source in the form of the single battery 2120. In thisillustrated embodiment, the pump 2108 is coupled to the battery 2120 viaa power lead 2122. The battery 2120 can be rechargeable battery, which,in some implementations, can be configured to be recharged wirelessly.The implantable power source 14 can have a variety of sizes, shapes, andconfigurations. It should be appreciated that the power source can haveother forms and/or can include a plurality of power sources. The battery2120 can be included as part of the pump 2108. Alternatively, as in thisillustrated embodiment, the battery 2120 can be a separate componentfrom the pump 2108 and can be configured to be in electroniccommunication therewith along a power line, e.g., the power lead 2122,etc. The battery 2120 can be implanted at an anatomical location outsidethe patient's lung, such as a shoulder of the patient, or in otheranatomical areas.

The pump 2108 can be configured to continuously pump fluid, e.g.,continuously pump fluid through the inflow port and out the outflowport. The pump 2108 can thus be configured to continuously pump fluidout of the area at which an input opening of the inflow tube coupled tothe inflow port is located, e.g., out of the patient's thoracic duct andinto the area at which an output opening of the outflow tube coupled tothe inflow port is located, e.g., into a vein of the patient such as thepatient's subclavian vein, internal jugular vein, innominate vein, orsuperior vena cava.

The pump 2108 can be configured to periodically pump fluid, e.g., havealternating periods of pumping and no pumping, based on informationacquired by one or more sensors. Operation of the pump 2108 iscontrolled by a controller 2130 schematically shown in FIG. 30. Thecontroller 2130 can be configured to be implanted in the patient's bodyand it can communicate with the pump 2108 via a wired or a wirelessconnection. The controller can be configured to cause the pump 2108 tonot pump (e.g., be in an idle state) until the occurrence of a triggerevent. In other words, the pump 2108 can have a default idle state andcan be configured to move between the default idle state and an activestate in which the pump 2108 pumps fluid in response to the triggerevent. The trigger event can be a dynamic trigger event generated basedon certain measurements acquired by the sensors.

In some implementations, a dynamic trigger event can include a value ofa measured parameter being out of range as compared to a threshold valueand/or threshold range of values. The parameter can be measured using asensor (not shown) associated with the patient having the pump 2108implanted therein. Examples of sensors that can be used to measure aparameter include pressure sensors (e.g., central venous pressure (CVP)or other fluid pressure sensors, and blood pressure sensors), radiofrequency transmitters and receivers, fluid sensors, bioimpedancesensors, heart rate sensors, breathing sensors, activity sensors,optical sensors. Pressure sensors can be placed, for example, in thepatient's venous system, in the patient's heart, in the patient'sarterial system, and/or in the patient's body at target anatomical sitesthat may suffer from an increase of interstitial fluid overload. Fluidsensors can be placed, for example, in the lungs. Examples of themeasured parameter include pressure (e.g., as measured by a pressuresensor), fluid amount (e.g., as measured by a fluid sensor),bioimpedance (e.g., as measured by a bioimpedance sensor), heart rate(e.g., as measured by a heart rate sensor), breathing rate (e.g., asmeasured by a breathing sensor), patient activity level (e.g., asmeasured by an activity sensor), and organ dimension (e.g., as measuredby an optical sensor). The sensor can be implanted in the patient aspart of the pump 2108, implanted in the patient as a separate componentfrom the pump 2108, or the sensor can be located external to thepatient, such as by being on a skin surface thereof. If not already apart of the pump 2108 so as to be in electronic communication therewith,the sensor can be configured to be in electronic communication with thepump 2108 over a communication line such as a wired line or a wirelessline. The sensor can include one or more sensors. In embodimentsincluding a plurality of sensors, each of the sensors can be configuredto measure the same parameter as or a different parameter than any oneor more of the other sensors.

Accordingly, in some implementations, one or more sensors as describedherein can be used to detect congestion in the form of accumulation offluid in the thoracic duct and the pump 2108 can be activateddynamically, in response to the detection of the congestion.Additionally or alternatively, the congestion can be detected based onmeasurements of current and/or voltage consumption by the pump 2108.

In some implementations, the pump 2108 can be configured to pump/notpump in response to a trigger event generated based on user input. Thepump 2108 can thus be configured for on-demand pumping. The user cantherefore cause pumping when desired (e.g., during a shortness of breathepisode, when the user notices a slight weight gain, etc.) which canhelp the pump 2108 run efficiently and when most needed as determined bythe user. The user can include the patient or another person, such asthe patient's doctor, the patient's caretaker, etc. The input can beprovided to the pump 2108 in a variety of ways. In an exemplaryembodiment, the input can be provided wirelessly to the pump 2108 usinga user-operated control device located external to the patient andconfigured to wirelessly communicate with the pump 2108 to cause thepump 2108 to start pumping (e.g., change the pump 2108 from the idlestate to the active state) or to stop pumping (e.g., change the pump2108 from the active state to the idle state).

Also, in some embodiments, the pump 2108 can be configured toperiodically pump on a set schedule, e.g., alternately pump for xminutes and not pump for y minutes, where “x” and “y” can be equal ordifferent. The set schedule can be preprogrammed into the pump 2108,e.g., in a controller thereof (discussed further below). The setschedule can be static or can be adjustable. The set schedule can beadjustable in a variety of ways, as will be appreciated by a personskilled in the art, such as by being wirelessly adjusted using auser-operated control device located external to the patient andconfigured to wirelessly communicate with the pump 2108 to adjust thepumping schedule thereof. Having a set schedule can allow the pump 2108to be relatively simple electronically and not require much processingcapability.

In at least some embodiments, the pump 2108 can be configured to changeits pumping rate (e.g., from zero to a non-zero value, from a non-zerovalue to zero, or from one non-zero value to another non-zero value)based on a fluid amount measured by a fluid sensor. If the measuredfluid amount exceeds a predetermined threshold maximum fluid amountvalue, the pump 2108 can be configured to increase its pump rate (e.g.,increase from zero or increase from some non-zero value) in an effort todecrease the amount of fluid present.

Also, in some embodiments, the pump 2108 can be configured to operate inmore than one mode, such that it can switch between being operated inresponse to a manual trigger (based on user input), in response to anevent defected based on sensor-acquired measurements (a dynamiccontrol), or based on a predetermined schedule. The switching betweenthem can be controlled based on user input or automatically.

The pump 2108 can include only a continuous mode of operation such thatthe pump 2108 can only continuously pump fluid, the pump 2108 caninclude only a periodic mode of operation such that the pump 2108 canonly periodically pump fluid, or the pump 2108 can include thecontinuous and periodic modes of operation and be configured to beselectively switched between the continuous mode of operation and theperiodic mode of operation. The mode switching can be accomplished in avariety of ways, as will be appreciated by a person skilled in the artsuch as by being wirelessly switched using a user-operated controldevice located external to the patient and configured to wirelesslycommunicate with the pump 2108 to change the mode of operation thereof.

The controller 2130 (e.g., a processor, a microcontroller, etc.) inelectronic communication with the pump 2108 can be configured tofacilitate control of the pump 2108, e.g., control changing the pump'smode of operation, etc. The controller can be included as part of thepump 2108 so as to be configured to be implanted in the patient with thepump 2108 or, as in this illustrated embodiment, the controller can be aseparate component from the pump 2108. The controller being part of thepump 2108 can help allow the pump 2108 to be a self-contained system,although in such a controller requires space in the pump 2108, which canincrease a size of the pump 2108. The controller being a separatecomponent from the pump 2108 can help the pump 2108 have a smaller sizeand/or can allow the pump 2108 to be controlled by a more powerfulprocessor since the processor can be more easily upgraded than ifimplanted with the pump 2108 and/or since the processor's size can beless important when outside the pump 2108 as opposed to inside the pump2108.

Each of the inflow and outflow tubes 2104, 2106 can be a multi-lumenchannel, with separate lumens to withdraw fluid from the thoracic ductto the pump 2108 and to direct fluid from the pump 2108 to the venoussystem. FIG. 31 illustrates an embodiment of a tube 2202 which can beany of the inflow or outflow tubes 2104, 2106. As shown, the tube 2202has a generally circular cross-section and includes first and secondlumens 2205 a, 2205 b which do not communicate with one another and thusprovide separate flows. The inflow and outflow tubes 2104, 2106 can havemore than two lumens. The first lumen 2205 a can be a suction lumen, andthe second lumen 2205 b can be a discharge lumen. For example, theinflow tube 2104 can have a third lumen for inflating an attachmentfeature 2124 when it is an expandable element such as a balloon-typeelement. The inflow and outflow tubes 2104, 2106 can have a diameterfrom about 1 mm to about 3 mm, from about 2 mm to about 3 mm, or otherdiameters such that the tubes can be disposed within the thoracic ductand the vein.

In some embodiments, each of the inflow or outflow tubes 2104, 2106 canhave a subcutaneous port accessible from outside of the patient's bodyand configured to be used to access the tubes 2104, 2106 to clean themwhen the implantable device 2100 is used over a prolonged period oftime. The cleaning can be performed between treatment periods, and itcan involve flushing the inflow and outflow tubes 2104, 2106 with anantiseptic solution. FIG. 32 illustrates an embodiment of a tube 2302which can be any of the inflow or outflow tubes 2104, 2106. As shown,the tube 2202 has a generally circular cross-section and includes firstand second lumens 2305 a, 2305 b which can be similar to the lumens 2205a, 2205 b shown in FIG. 31. The tube 2302 has a subcutaneous port 2310that can be used to clean the inflow and outflow tubes 2104, 2106 aspart of maintenance of the implantable device 2100. The port 2310 can bemanufactured from an elastomeric material and can be used to inject anantiseptic or other solution into the inflow and outflow tubes 2104,2106 and to remove the solution from the tubes 2104, 2106 after it hasbeen used.

In some embodiments, as shown in FIG. 33, each of the inflow and outflowtubes 2104, 2106 has a protective element configured to preventcontamination of the implantable device 2100. The protective element canbe in the form of a cuff 2402 or other barrier that is disposed aroundthe tubes 2104, 2106 in the vicinity of subcutaneous ports 2404, 2406accessible from outside of the patient's body. The subcutaneous ports2404, 2406 are configured to be used to access the tubes 2104, 2106 forcleaning or other purposes. The cuff 2402 protects contamination of theblood stream and thus reduces a possibility of infection. The cuff 2402can be in the form of a sponge or other material including anantimicrobial agent. The material can be slow-releasing material whichreleases the antimicrobial agent slowly, over an extended time period.

The ostial valve of the thoracic duct is opened at low vein wall tensionand closed at high venous wall tension. Therefore, patients withdistended jugular pressure may exhibit low lymphatic flow due to closureof the ostial valve of the thoracic duct. FIGS. 34A and 34B illustrateexamples of stents or stent-like devices 2502 and 2504 that can beimplanted to alleviate the ostial valve closure by enabling the valve torelease the lymph fluid. The stents can be configured to expand(corresponding to an activated configuration) and constrict(corresponding to a relaxed configuration). The stent-like device 2502can be tapered and has a rounded tip 2503. The stent-like device 2504can also be tapered and has a slanted tip 2505. The stent-like devices2502 and 2504 can have a variety of other configurations. The stent-likedevices 2502 and 2504 can include a valve (e.g., a duckbill valve orvalve of another type(s)) (not shown) configured to cause release of thelymph fluid. The devices 2502 and 2504 can be manufactured from suchmaterial such as, e.g., polytetrafluoroethylene (ePTFE). The stent-likedevices 2502 and 2504 can be attached to the inflow tube 2104 and canadditionally be used for anchoring the inflow tube 2104 within thethoracic duct. In some embodiments, the stent-like devices 2502 and 2504can be connected to an implanted pump (e.g., the pump 2108 in FIG. 30)and function as an inlet port.

FIGS. 34C and 34D illustrate an example of one embodiment of deploymentof a stent 2510 in a thoracic duct (not shown) of a patient, such aswithin the ostial valve of the thoracic duct. The stent 2510, shownpartially in FIGS. 34C and 34D, can be any of the stent-like devices2502 and 2504, or a stent having another configuration. As shown in FIG.34C, the stent 2510 is inserted into an inner tube 2514 extendingthrough a sheath 2516 of an inserter disposed in the thoracic duct. InFIG. 34C, the stent 2510 is inserted in a compressed or unexpandedconfiguration. The stent 2510 is inserted over a guidewire 2518extending through the inner tube 2514, as also shown in FIG. 34C. Afterthe stent 2510 is inserted, the sheath 2516 can be retrieved by a user(e.g., any medical personnel) while holding the inner tube 2514 inplace, as shown in FIG. 34D, to thus cause the stent 2510 to move to anexpanded configuration to thereby alleviate the ostial valve closure byenabling the valve to release the lymph fluid. The guidewire 2518 andthe inner tube 2514 may then be removed.

The pump 2108 can be implanted in a subcutaneous pocket created for thepump 2108, which can help ensure that the pump 2108 has adequate spacewithin the patient's body. In the exemplary embodiment (FIG. 30), thepump 2108 can be implanted adjacent the junction of the internal jugularvein of the patient and the left subclavian vein of the patient, wherethe patient's thoracic duct and lymphatic duct (e.g., the rightlymphatic duct) drain. For patients at risk of developing edema, outflowpressure at the junction is typically highly elevated, e.g., to valuesgreater than about 10 mmHg, over normal outflow pressure, e.g., about 5mmHg. Providing the pump 2108 can help regulate fluid at the junction,it can help prevent edema from occurring. The pump 2108 can beconfigured to regulate the pressure at the junction to which it isadjacent to a safe, non-edemic level such as its normal level, e.g.,about 5 mmHg, or within a range of about 2 to 6 mmHg. The pressuregradient that that pump 2108 discharges against is less than about 15mmHg. This relatively low flow rate and this pressure gradient can allowthe pump 2108 to function with a very low energy consumption (e.g., witha low drain on the battery 2120), can allow for a very small powersource (e.g., a very small battery such as those used with pacemakersand implantable cardioverter-defibrillators (ICDs)), and/or can allowfor the pump 2108 to be very small and thereby facilitate implantationthereof.

FIG. 35 illustrates of one embodiment of a method 2600 of treating edema(e.g., fluid overload) using an implantable device (e.g., theimplantable device 2100 in FIG. 30) in accordance with the describedtechniques. The method 2600 includes gaining an intravenous (IV) accessto the thoracic duct, at block 2602. This can involve placing aguidewire towards the treatment site. The method 2600 further includespreparing, at block 2604, a subcutaneous pocket in a patient to seat theimplantable pump (e.g., the pump 2108) therein. The subcutaneous pocketcan be created, or, if such pocket already exists, it can be preparedfor receiving the pump therein. Although not shown as a separate step,the method 2600 can also include subcutaneously creating a tunnelbetween the subcutaneous pocket and the IV access point.

The method 2600 can also include verifying a location of the patient'sthoracic duct and/or the patient's lymphatic duct (e.g., the rightlymphatic duct), which can help a surgeon and/or other medicalprofessional involved in performing a surgical procedure that includesimplanting, at block 2606, the pump verify that the pump, an inflow tubecoupled to the pump, and/or an outflow tube coupled to the pump areimplanted in the correct locations within the patient. If any one ormore of the pump, the inflow tube, and the outflow tube is beingimplanted in one of the patient's thoracic duct and/or the patient'slymphatic duct, the location at least that one of the thoracic duct andlymphatic duct can be verified to help ensure that the pump, the inflowtube, and/or the outflow tube are implanted at the desired location(s).The verification can be performed in any of a variety of ways, as willbe appreciated by a person skilled in the art, such as by using animaging technique such as echo or fluoroscopy. The verification of thelocation of the patient's thoracic duct (and/or the patient's (right)lymphatic duct) and occur after the implantation of the pump such thatthe implanted location of the pump can be determined in view of theverification and adjusted if need be in view of the verification.Additionally or alternatively, the verification can be performed priorto the implantation of the pump.

After the pump is inserted into the subcutaneous pocket, the inflow andoutflow tubes (e.g., the inflow and outflow tubes 2104, 2106 in FIG. 30)are positioned, at block 2608, in the patient such that their respectiveinflow and outflow openings are desirably positioned. The positioning ofthe inflow and outflow tubes can involve dilatation of the IV access,introduction of an introducer (e.g., a peel-away sheath) through the IVaccess, and insertion of the pump tubes through the introducer, and peelaway sheath. After that, the inflow tube is removably anchored withinthe thoracic duct (e.g., using the attachment feature 2124 shown in FIG.30), and the outflow tube is positioned within the vein, such as thejugular, subclavian, or innominate vein. The introducer can then beremoved from the treatment site. The guidewire can be removed when it isno longer needed. The inflow and outflow tubes can be positioned (2608)in a variety of ways, as will be appreciated by a person skilled in theart, such as by using a central line procedure. Positioning tubes suchas catheters is further described in U.S. application Ser. No.14/625,930 entitled “System And Method For Treating Pulmonary Edema,”filed Feb. 19, 2015. Other examples of a method of treating pulmonaryedema using an implantable pump are described in U.S. application Ser.No. 14/726,715 entitled “Systems and Methods for Treating PulmonaryEdema,” filed Jun. 1, 2015.

In some embodiments, as in the example of FIG. 35, one or more sensors(e.g., pressure sensors or other type(s) of sensors) can be implanted.It should be appreciated however the sensor in some embodiments is notimplanted and is instead located outside the patient's body, and/or atleast one sensor is implanted and at least one sensor is located outsidethe patient's body. As another variation, the sensor(s) may not need tobe implanted separately, as it can be included with one or more othercomponents of the implantable device.

The method 2600 also involves implanting a battery, at block 2612. Itshould be appreciated that the order of the steps shown in FIG. 35 isexemplary only, and that the battery can be implanted, e.g., before oneor more sensors are implanted, or at any other time. Also, the order ofthe other steps is exemplary only. Before the battery is implanted, alocation for it can be prepared within the patient's body.

After the pump is implanted (2606), the inflow and outflow tubes arepositioned (2608), the sensor is optionally implanted (2610), and thebattery is implanted (2612), the method includes controlling fluid flowwith the pump of the implantable device, at block 2614. The control cangenerally occur as described above. In at least some embodiments,controlling of the pump can include continuously running the pump whichcan involve operating the pump in an idle mode and activating it inresponse to a trigger. The selection of one or more modes of operationof the pump can be done based on the patient's characteristics, acondition being treated, etc. The implantable device implanted into thepatient's body as discussed above can then operate to alleviate chronicfluid overload conditions in the patient.

The described techniques discussed above relate to using an implantabledevice for treatment of chronic fluid overload, which can result inedema, such as pulmonary edema. In some circumstances, it may be desiredto implant into a patient's body a system or device that can be used fora rapid alleviation of fluid overload. In such circumstances, thepatient may not need to have the pump implanted in his/her bodyimplanted for an extended period of time. At the same time, the patientmay be at risk of developing fluid overload symptoms, and a rapidresponse can be required to address this condition. FIGS. 36 and 37illustrate such alternative embodiment of an implantable device (whichcan have a single or dual chamber) 2700 having an access port 2702. Thedevice 2700 with the port 2702 can be implanted subcutaneously, while apump may not be implanted. The device 2700 can have or can be coupled tosubcutaneously implanted inlet or inflow tube 2704 and outlet or outflowtube 2706, which can be similar to the inflow and outflow tubes 2104,2106 (FIG. 30), respectively. Also, the inflow and outflow tubes 2704,2706 can be placed within the patient's body similar to the tubes 2104,2106 as shown in FIG. 30, or other can be placed in other locations. Itshould be appreciated that the implantable device 2700 and the tubes2704, 2706 can have any other components and feature not shown hereinfor the sake of simplicity.

When a treatment (e.g., active pumping) is required, the tubes 2704,2706 can be accessed via the port 2702 and can be used to allow thelymphatic fluids to flow more easily and thus reduce the edema. The port2702 can be accessed externally using, e.g., a needle and it can becoupled to an external pump 2712, such as a peristaltic pump or othertype of pump, as shown in FIG. 37. After the use, the tubes 2704, 2706can be removed, whereas the port 2702 can remain implanted within thepatient's body. If a subsequent treatment is required, a new set ofinflow and outflow tubes can be introduced, the tubes can be connectedto the external pump, and the treatment can be performed for a desiredperiod of time, which can be from about 2 hours to about 2 days. Thetubes can then be removed and, if still desired, the device 2700 withthe port 2702 can remain implanted. In this way, the accessible systemfor multiple “on-demand” treatments is provided.

In the described embodiments, as mentioned above, a component or featureof any one of the embodiments can be used in combination with any othercomponent or feature of another embodiment. Thus, if a certain featureis not described in a connection with one embodiment while it is shownin connection with another embodiment, it should be appreciated that theformer embodiment may have that feature. Non-limiting examples of suchfeatures include various sensors, control elements, various types oflumens, fixation elements used to attached the catheter to the patient,etc.

It should be appreciated that the systems and methods disclosed hereincan be used with a variety of surgical devices, including measuringdevices, sensing devices, locator devices, insertion devices, etc. Itshould further be appreciated that the systems and methods describedherein can have various modifications and variations. For example, anyof the implantable catheter systems described herein can have first(e.g., distal) and second (e.g., proximal) selectively deployablerestriction members having approximately the same or different diametersonce deployed. The restriction members can be deployed in any suitableorder. For example, in some embodiments, the distal restriction membercan be deployed prior to deployment of the proximal restriction members.However, in some embodiments, the distal and proximal restrictionmembers can be deployed such that the proximal restriction member isdeployed first.

Furthermore, in some embodiments, the catheter system can be fullycannulated, such that a guide wire can be received therethrough. In someembodiments, a motor configured to rotate a drive shaft and therebyrotate an impeller coupled to the drive shaft is cannulated and can thusalso receive a guidewire therethrough. As discussed above, each of thedescribed catheter systems can have one or more pressure, or other typesof sensors that can be disposed at suitable locations to monitor variousparameters at a low pressure zone created in the patient's vein(s), aswell as at other locations.

One skilled in the art will appreciate further features and advantagesof the described subject matter based on the above-describedembodiments. Accordingly, the present disclosure is not to be limited bywhat has been particularly shown and described, except as indicated bythe appended claims. All publications and references cited herein areexpressly incorporated herein by reference in their entirety.

1-21. (canceled)
 22. A device for treatment of edema, the devicecomprising: an elongate member sized to fit within a body lumen; animpeller housing having an impeller therein coupled to the elongatemember; and a restrictor coupled to the impeller housing to form aconical lumen through the restrictor and the impeller housing.
 23. Thedevice of claim 22, wherein the restrictor is coupled to the elongatemember by a membrane.
 24. The device of claim 23, wherein the restrictoris proximal to impeller housing and the membrane tapers from therestrictor to the impeller housing to define the conical lumen.
 25. Thedevice of claim 24, wherein the restrictor is mounted on a support ringat a proximal end of the tapered membrane, wherein the support ringcomprises a guide channel holding a drive shaft of the impeller.
 26. Thedevice of claim 22, wherein the impeller housing comprises one or morewindows along a distal portion thereof.
 27. The device of claim 26,further comprising an atraumatic tip extending distally of the impellerhousing.
 28. The device of claim 22, further comprising a driveshaftextending at least partially through the elongate member.
 29. The deviceof claim 22, wherein the restrictor comprises an inflatable balloon, theelongate member further comprising an inflation lumen extending at leastpartially therethrough.
 30. The device of claim 22, further comprising asheath through which the elongate member is slideably disposed.
 31. Thedevice of claim 30, wherein the sheath comprises a second restrictor.32. A method of treating edema, the method comprising: positioning, in avessel near a thoracic output duct, a device comprising a taperedconduit; and mechanically pumping blood through the device, from a wideend of the conduit to a narrow end to thereby lower pressure near thethoracic output duct.
 33. The method of claim 32, wherein the devicecomprises a restrictor with an opening therethrough and a housingmember, and the tapered conduit is provided by a membrane that tapersfrom the opening to the housing member, and further wherein the blood ispumped by operating an impeller within the device.
 34. The method ofclaim 33, wherein the restrictor occludes the vessel but for the openingtherethrough.
 35. The method of claim 34, wherein the vessel is ajugular vein.
 36. The method of claim 33, wherein the housing memberhouses the impeller, the device further comprising an elongatedriveshaft extending proximally from the impeller.
 37. The method ofclaim 36, wherein positioning the device includes pushing the elongatedriveshaft into the body lumen.
 38. The method of claim 36, wherein theblood flows out of the housing member via one or more aperture along theside of the housing member.
 39. The method of claim 36, whereinpositioning the device includes inserting a sheath through which theelongate member is slideably disposed.
 40. The method of claim 39,wherein the sheath comprises a second restrictor.
 41. The method ofclaim 33, wherein the restrictor comprises an inflatable balloon and themethod further comprises inflating the balloon when the device ispositioned in the body lumen.